Merge pull request #212 from aeternity/GH-211-prepare_release_4_2_0

Prepare release 4.2.0
Bump version to 4.2.0 and fix CHANGELOG
2020-01-15 11:58:47 +01:00 · 2020-01-15 11:39:25 +01:00 · 2020-01-15 09:41:03 +01:00 · 2019-12-16 17:04:49 +01:00 · 2019-12-16 17:04:49 +01:00 · 2019-12-16 17:04:49 +01:00
39 changed files with 1829 additions and 681 deletions
@@ -9,28 +9,52 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 ### Removed

-## [4.0.0-rc3] - 2019-09-12
+## [4.2.0] - 2020-01-15
 ### Added
+- Allow separate entrypoint/function type signature and definition, and pattern
+  matching in left-hand sides:
+  ```
+    function
+      length : list('a) => int
+      length([])      = 0
+      length(x :: xs) = 1 + length(xs)
+  ```
+- Allow pattern matching in list comprehension generators (filtering out match
+  failures):
+  ```
+    function somes(xs : list(option('a))) : list('a) =
+      [ x | Some(x) <- xs ]
+  ```
+- Allow pattern matching in let-bindings (aborting on match failures):
+  ```
+    function test(m : map(int, int)) =
+        let Some(x) = Map.lookup(m, 0)
+        x
+  ```
+### Changed
+- FATE code generator improvements.
+- Bug fix: Handle qualified constructors in patterns.
+- Bug fix: Allow switching also on negative numbers.
+### Removed
+
+## [4.1.0] - 2019-11-26
+### Added
+- Support encoding and decoding bit fields in call arguments and results.
+### Changed
+- Various improvements to FATE code generator.
+### Removed
+
+## [4.0.0] - 2019-10-11
+### Added
+- `Address.to_contract` - casts an address to a (any) contract type.
+- Pragma to check compiler version, e.g. `@compiler >= 4.0`.
+- Handle numeric escapes, i.e. `"\x19Ethereum Signed Message:\n"`, and similar strings.
 - `Bytes.concat` and `Bytes.split` are added to be able to
  (de-)construct byte arrays.
 - `[a..b]` language construct, returning the list of numbers between
  `a` and `b` (inclusive). Returns the empty list if `a` > `b`.
 - [Standard libraries] (https://github.com/aeternity/protocol/blob/master/contracts/sophia_stdlib.md)
 - Checks that `init` is not called from other functions.
-### Changed
- Error messages are changed into a uniform format, and more helpful
-  messages have been added.
- `Crypto.<hash_fun>` and `String.<hash_fun>` for byte arrays now only
-  hash the actual byte array - not the internal ABI format.
- More strict checks for polymorphic oracles and higher order oracles
-  and entrypoints.
- `AENS.claim` is updated with a `NameFee` field - to be able to do
-  name auctions within contracts.
- Fixed a bug in `Bytes.to_str` for AEVM.
-### Removed
-
-## [4.0.0-rc1] - 2019-08-22
-### Added
 - FATE backend - the compiler is able to produce VM code for both `AEVM` and `FATE`. Many
  of the APIs now take `{backend, aevm | fate}` to decide wich backend to produce artifacts
  for.
@@ -47,6 +71,20 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  that shall be able to receive funds should be marked as payable. `Address.is_payable(a)`
  can be used to check if an (contract) address is payable or not.
 ### Changed
+- Nice type error if contract function is called as from a namespace.
+- Fail on function definitions in contracts other than the main contract.
+- Bug fix in variable optimization - don't discard writes to the store/state.
+- Bug fixes in error reporting.
+- Bug fix in variable liveness analysis for FATE.
+- Error messages are changed into a uniform format, and more helpful
+  messages have been added.
+- `Crypto.<hash_fun>` and `String.<hash_fun>` for byte arrays now only
+  hash the actual byte array - not the internal ABI format.
+- More strict checks for polymorphic oracles and higher order oracles
+  and entrypoints.
+- `AENS.claim` is updated with a `NameFee` field - to be able to do
+  name auctions within contracts.
+- Fixed a bug in `Bytes.to_str` for AEVM.
 - New syntax for tuple types. Now 0-tuple type is encoded as `unit` instead of `()` and
  regular tuples are encoded by interspersing inner types with `*`, for instance `int * string`.
  Parens are not necessary. Note it only affects the types, values remain as their were before,
@@ -154,9 +192,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Simplify calldata creation - instead of passing a compiled contract, simply
  pass a (stubbed) contract string.

-[Unreleased]: https://github.com/aeternity/aesophia/compare/v4.0.0-rc3...HEAD
-[4.0.0-rc3]: https://github.com/aeternity/aesophia/compare/v4.0.0-rc1...v4.0.0-rc3
-[4.0.0-rc1]: https://github.com/aeternity/aesophia/compare/v3.2.0...v4.0.0-rc1
+[Unreleased]: https://github.com/aeternity/aesophia/compare/v4.2.0...HEAD
+[4.2.0]: https://github.com/aeternity/aesophia/compare/v4.2.0...v4.1.0
+[4.1.0]: https://github.com/aeternity/aesophia/compare/v4.1.0...v4.0.0
+[4.0.0]: https://github.com/aeternity/aesophia/compare/v4.0.0...v3.2.0
 [3.2.0]: https://github.com/aeternity/aesophia/compare/v3.1.0...v3.2.0
 [3.1.0]: https://github.com/aeternity/aesophia/compare/v3.0.0...v3.1.0
 [3.0.0]: https://github.com/aeternity/aesophia/compare/v2.1.0...v3.0.0
@@ -2,7 +2,7 @@

 {erl_opts, [debug_info]}.

-{deps, [ {aebytecode, {git, "https://github.com/aeternity/aebytecode.git", {ref,"a66dc0a"}}}
+{deps, [ {aebytecode, {git, "https://github.com/aeternity/aebytecode.git", {ref,"4f4d6d3"}}}
       , {getopt, "1.0.1"}
       , {eblake2, "1.0.0"}
       , {jsx, {git, "https://github.com/talentdeficit/jsx.git",
@@ -15,7 +15,7 @@
            {base_plt_apps, [erts, kernel, stdlib, crypto, mnesia]}
           ]}.

-{relx, [{release, {aesophia, "4.0.0-rc3"},
+{relx, [{release, {aesophia, "4.2.0"},
         [aesophia, aebytecode, getopt]},

        {dev_mode, true},
@@ -1,7 +1,7 @@
 {"1.1.0",
 [{<<"aebytecode">>,
  {git,"https://github.com/aeternity/aebytecode.git",
-       {ref,"a66dc0a97facdeaad7e5403018ad195d989e4793"}},
+       {ref,"4f4d6d30cd2c46b3830454d650a424d513f69134"}},
  0},
 {<<"aeserialization">>,
  {git,"https://github.com/aeternity/aeserialization.git",
@@ -129,7 +129,7 @@ encode_anon_args(Types) ->

 encode_args(Args) -> [ encode_arg(A) || A <- Args ].

-encode_arg({arg, _, Id, T}) ->
+encode_arg({typed, _, Id, T}) ->
    #{name => encode_type(Id),
      type => encode_type(T)}.

@@ -60,7 +60,8 @@

 -record(is_contract_constraint,
    { contract_t :: utype(),
-      context    :: aeso_syntax:expr()  %% The address literal
+      context    :: {contract_literal, aeso_syntax:expr()} |
+                    {address_to_contract, aeso_syntax:ann()}
    }).

 -type field_constraint() :: #field_constraint{} | #record_create_constraint{} | #is_contract_constraint{}.
@@ -83,7 +84,7 @@
 -type qname() :: [string()].
 -type typesig() :: {type_sig, aeso_syntax:ann(), type_constraints(), [aeso_syntax:named_arg_t()], [type()], type()}.

-type type_constraints() :: none | bytes_concat | bytes_split.
+-type type_constraints() :: none | bytes_concat | bytes_split | address_to_contract.

 -type fun_info()  :: {aeso_syntax:ann(), typesig() | type()}.
 -type type_info() :: {aeso_syntax:ann(), typedef()}.
@@ -110,7 +111,7 @@
    , in_pattern = false              :: boolean()
    , stateful   = false              :: boolean()
    , current_function = none         :: none | aeso_syntax:id()
-    , what       = top                :: top | namespace | contract
+    , what       = top                :: top | namespace | contract | main_contract
    }).

 -type env() :: #env{}.
@@ -175,12 +176,13 @@ bind_fun(X, Type, Env) ->
    end.

 -spec force_bind_fun(name(), type() | typesig(), env()) -> env().
-force_bind_fun(X, Type, Env) ->
+force_bind_fun(X, Type, Env = #env{ what = What }) ->
    Ann    = aeso_syntax:get_ann(Type),
    NoCode = get_option(no_code, false),
-    Entry = case X == "init" andalso Env#env.what == contract andalso not NoCode of
-                true  -> {reserved_init, Ann, Type};
-                false -> {Ann, Type}
+    Entry = if X == "init", What == main_contract, not NoCode ->
+                    {reserved_init, Ann, Type};
+               What == contract -> {contract_fun, Ann, Type};
+               true -> {Ann, Type}
            end,
    on_current_scope(Env, fun(Scope = #scope{ funs = Funs }) ->
                            Scope#scope{ funs = [{X, Entry} | Funs] }
@@ -306,6 +308,9 @@ lookup_env1(#env{ namespace = Current, scopes = Scopes }, Kind, Ann, QName) ->
                {reserved_init, Ann1, Type} ->
                    type_error({cannot_call_init_function, Ann}),
                    {QName, {Ann1, Type}};  %% Return the type to avoid an extra not-in-scope error
+                {contract_fun, Ann1, Type} ->
+                    type_error({contract_treated_as_namespace, Ann, QName}),
+                    {QName, {Ann1, Type}};
                {Ann1, _} = E ->
                    %% Check that it's not private (or we can see private funs)
                    case not is_private(Ann1) orelse AllowPrivate of
@@ -519,6 +524,7 @@ global_env() ->
    %% Conversion
    IntScope     = #scope{ funs = MkDefs([{"to_str", Fun1(Int,     String)}]) },
    AddressScope = #scope{ funs = MkDefs([{"to_str", Fun1(Address, String)},
+                                          {"to_contract", FunC(address_to_contract, [Address], A)},
                                          {"is_oracle", Fun1(Address, Bool)},
                                          {"is_contract", Fun1(Address, Bool)},
                                          {"is_payable", Fun1(Address, Bool)}]) },
@@ -582,7 +588,8 @@ infer1(Env, [], Acc, _Options) -> {Env, lists:reverse(Acc)};
 infer1(Env, [{contract, Ann, ConName, Code} | Rest], Acc, Options) ->
    %% do type inference on each contract independently.
    check_scope_name_clash(Env, contract, ConName),
-    {Env1, Code1} = infer_contract_top(push_scope(contract, ConName, Env), contract, Code, Options),
+    What = if Rest == [] -> main_contract; true -> contract end,
+    {Env1, Code1} = infer_contract_top(push_scope(contract, ConName, Env), What, Code, Options),
    Contract1 = {contract, Ann, ConName, Code1},
    Env2 = pop_scope(Env1),
    Env3 = bind_contract(Contract1, Env2),
@@ -591,7 +598,10 @@ infer1(Env, [{namespace, Ann, Name, Code} | Rest], Acc, Options) ->
    check_scope_name_clash(Env, namespace, Name),
    {Env1, Code1} = infer_contract_top(push_scope(namespace, Name, Env), namespace, Code, Options),
    Namespace1 = {namespace, Ann, Name, Code1},
-    infer1(pop_scope(Env1), Rest, [Namespace1 | Acc], Options).
+    infer1(pop_scope(Env1), Rest, [Namespace1 | Acc], Options);
+infer1(Env, [{pragma, _, _} | Rest], Acc, Options) ->
+    %% Pragmas are checked in check_modifiers
+    infer1(Env, Rest, Acc, Options).

 check_scope_name_clash(Env, Kind, Name) ->
    case get_scope(Env, qname(Name)) of
@@ -602,7 +612,7 @@ check_scope_name_clash(Env, Kind, Name) ->
            destroy_and_report_type_errors(Env)
    end.

-spec infer_contract_top(env(), contract | namespace, [aeso_syntax:decl()], list(option())) ->
+-spec infer_contract_top(env(), main_contract | contract | namespace, [aeso_syntax:decl()], list(option())) ->
    {env(), [aeso_syntax:decl()]}.
 infer_contract_top(Env, Kind, Defs0, _Options) ->
    Defs = desugar(Defs0),
@@ -610,11 +620,13 @@ infer_contract_top(Env, Kind, Defs0, _Options) ->

 %% infer_contract takes a proplist mapping global names to types, and
 %% a list of definitions.
-spec infer_contract(env(), contract | namespace, [aeso_syntax:decl()]) -> {env(), [aeso_syntax:decl()]}.
-infer_contract(Env0, What, Defs) ->
+-spec infer_contract(env(), main_contract | contract | namespace, [aeso_syntax:decl()]) -> {env(), [aeso_syntax:decl()]}.
+infer_contract(Env0, What, Defs0) ->
+    Defs = process_blocks(Defs0),
    Env  = Env0#env{ what = What },
    Kind = fun({type_def, _, _, _, _})    -> type;
              ({letfun, _, _, _, _, _})   -> function;
+              ({fun_clauses, _, _, _, _}) -> function;
              ({fun_decl, _, _, _})       -> prototype;
              (_)                         -> unexpected
           end,
@@ -625,15 +637,18 @@ infer_contract(Env0, What, Defs) ->
    Env2 =
        case What of
            namespace     -> Env1;
-            contract  -> bind_state(Env1)   %% bind state and put
+            contract      -> Env1;
+            main_contract -> bind_state(Env1)   %% bind state and put
        end,
    {ProtoSigs, Decls} = lists:unzip([ check_fundecl(Env1, Decl) || Decl <- Get(prototype) ]),
    Env3      = bind_funs(ProtoSigs, Env2),
    Functions = Get(function),
    %% Check for duplicates in Functions (we turn it into a map below)
-    _         = bind_funs([{Fun, {tuple_t, Ann, []}} || {letfun, Ann, {id, _, Fun}, _, _, _} <- Functions],
-                          #env{}),
-    FunMap    = maps:from_list([ {Fun, Def} || Def = {letfun, _, {id, _, Fun}, _, _, _} <- Functions ]),
+    FunBind   = fun({letfun, Ann, {id, _, Fun}, _, _, _})   -> {Fun, {tuple_t, Ann, []}};
+                   ({fun_clauses, Ann, {id, _, Fun}, _, _}) -> {Fun, {tuple_t, Ann, []}} end,
+    FunName   = fun(Def) -> {Name, _} = FunBind(Def), Name end,
+    _         = bind_funs(lists:map(FunBind, Functions), #env{}),
+    FunMap    = maps:from_list([ {FunName(Def), Def} || Def <- Functions ]),
    check_reserved_entrypoints(FunMap),
    DepGraph  = maps:map(fun(_, Def) -> aeso_syntax_utils:used_ids(Def) end, FunMap),
    SCCs      = aeso_utils:scc(DepGraph),
@@ -644,6 +659,30 @@ infer_contract(Env0, What, Defs) ->
    destroy_and_report_type_errors(Env4),
    {Env4, TypeDefs ++ Decls ++ Defs1}.

+%% Restructure blocks into multi-clause fundefs (`fun_clauses`).
+-spec process_blocks([aeso_syntax:decl()]) -> [aeso_syntax:decl()].
+process_blocks(Decls) ->
+    lists:flatmap(
+      fun({block, Ann, Ds}) -> process_block(Ann, Ds);
+         (Decl)             -> [Decl] end, Decls).
+
+-spec process_block(aeso_syntax:ann(), [aeso_syntax:decl()]) -> [aeso_syntax:decl()].
+process_block(_, []) -> [];
+process_block(_, [Decl]) -> [Decl];
+process_block(Ann, [Decl | Decls]) ->
+    IsThis = fun(Name) -> fun({letfun, _, {id, _, Name1}, _, _, _}) -> Name == Name1;
+                             (_) -> false end end,
+    case Decl of
+        {fun_decl, Ann1, Id = {id, _, Name}, Type} ->
+            {Clauses, Rest} = lists:splitwith(IsThis(Name), Decls),
+            [{fun_clauses, Ann1, Id, Type, Clauses} |
+             process_block(Ann, Rest)];
+        {letfun, Ann1, Id = {id, _, Name}, _, _, _} ->
+            {Clauses, Rest} = lists:splitwith(IsThis(Name), [Decl | Decls]),
+            [{fun_clauses, Ann1, Id, {id, [{origin, system} | Ann1], "_"}, Clauses} |
+             process_block(Ann, Rest)]
+    end.
+
 -spec check_typedefs(env(), [aeso_syntax:decl()]) -> {env(), [aeso_syntax:decl()]}.
 check_typedefs(Env = #env{ namespace = Ns }, Defs) ->
    create_type_errors(),
@@ -704,18 +743,45 @@ check_unexpected(Xs) ->

 check_modifiers(Env, Contracts) ->
    create_type_errors(),
-    [ case C of
-          {contract, _, Con, Decls}  ->
+    check_modifiers_(Env, Contracts),
+    destroy_and_report_type_errors(Env).
+
+check_modifiers_(Env, [{contract, _, Con, Decls} | Rest]) ->
+    IsMain = Rest == [],
    check_modifiers1(contract, Decls),
    case {lists:keymember(letfun, 1, Decls),
            [ D || D <- Decls, aeso_syntax:get_ann(entrypoint, D, false) ]} of
        {true, []} -> type_error({contract_has_no_entrypoints, Con});
-                  _          -> ok
+        _ when not IsMain ->
+            case [ {Ann, Id} || {letfun, Ann, Id, _, _, _} <- Decls ] of
+                [{Ann, Id} | _] -> type_error({definition_in_non_main_contract, Ann, Id});
+                [] -> ok
            end;
-          {namespace, _, _, Decls} -> check_modifiers1(namespace, Decls);
-          Decl -> type_error({bad_top_level_decl, Decl})
-      end || C <- Contracts ],
-    destroy_and_report_type_errors(Env).
+        _ -> ok
+    end,
+    check_modifiers_(Env, Rest);
+check_modifiers_(Env, [{namespace, _, _, Decls} | Rest]) ->
+    check_modifiers1(namespace, Decls),
+    check_modifiers_(Env, Rest);
+check_modifiers_(Env, [{pragma, Ann, Pragma} | Rest]) ->
+    check_pragma(Env, Ann, Pragma),
+    check_modifiers_(Env, Rest);
+check_modifiers_(Env, [Decl | Rest]) ->
+    type_error({bad_top_level_decl, Decl}),
+    check_modifiers_(Env, Rest);
+check_modifiers_(_Env, []) -> ok.
+
+-spec check_pragma(env(), aeso_syntax:ann(), aeso_syntax:pragma()) -> ok.
+check_pragma(_Env, Ann, {compiler, Op, Ver}) ->
+    case aeso_compiler:numeric_version() of
+        {error, Err}  -> type_error({failed_to_get_compiler_version, Err});
+        {ok, Version} ->
+            Strip = fun(V) -> lists:reverse(lists:dropwhile(fun(X) -> X == 0 end, lists:reverse(V))) end,
+            case apply(erlang, Op, [Strip(Version), Strip(Ver)]) of
+                true  -> ok;
+                false -> type_error({compiler_version_mismatch, Ann, Version, Op, Ver})
+            end
+    end.

 -spec check_modifiers1(contract | namespace, [aeso_syntax:decl()] | aeso_syntax:decl()) -> ok.
 check_modifiers1(What, Decls) when is_list(Decls) ->
@@ -749,9 +815,9 @@ check_type(Env, T) ->
 check_type(Env, T = {tvar, _, _}, Arity) ->
    [ type_error({higher_kinded_typevar, T}) || Arity /= 0 ],
    check_tvar(Env, T);
-check_type(_Env, X = {id, _, "_"}, Arity) ->
+check_type(_Env, X = {id, Ann, "_"}, Arity) ->
    ensure_base_type(X, Arity),
-    X;
+    fresh_uvar(Ann);
 check_type(Env, X = {Tag, _, _}, Arity) when Tag == con; Tag == qcon; Tag == id; Tag == qid ->
    case lookup_type(Env, X) of
        {Q, {_, Def}} ->
@@ -783,7 +849,8 @@ check_type(_Env, Type = {uvar, _, _}, Arity) ->
    ensure_base_type(Type, Arity),
    Type;
 check_type(_Env, {args_t, Ann, Ts}, _) ->
-    type_error({new_tuple_syntax, Ann, Ts}).
+    type_error({new_tuple_syntax, Ann, Ts}),
+    {tuple_t, Ann, Ts}.

 ensure_base_type(Type, Arity) ->
    [ type_error({wrong_type_arguments, Type, Arity, 0}) || Arity /= 0 ],
@@ -921,8 +988,9 @@ typesig_to_fun_t({type_sig, Ann, _Constr, Named, Args, Res}) ->

 infer_letrec(Env, Defs) ->
    create_constraints(),
-    Funs = [{Name, fresh_uvar(A)}
-                 || {letfun, _, {id, A, Name}, _, _, _} <- Defs],
+    Funs = lists:map(fun({letfun, _, {id, Ann, Name}, _, _, _})   -> {Name, fresh_uvar(Ann)};
+                        ({fun_clauses, _, {id, Ann, Name}, _, _}) -> {Name, fresh_uvar(Ann)}
+                     end, Defs),
    ExtendEnv = bind_funs(Funs, Env),
    Inferred =
        [ begin
@@ -941,26 +1009,51 @@ infer_letrec(Env, Defs) ->
    [print_typesig(S) || S <- TypeSigs],
    {TypeSigs, NewDefs}.

-infer_letfun(Env0, {letfun, Attrib, Fun = {id, NameAttrib, Name}, Args, What, Body}) ->
+infer_letfun(Env, {fun_clauses, Ann, Fun = {id, _, Name}, Type, Clauses}) ->
+    Type1 = check_type(Env, Type),
+    {NameSigs, Clauses1} = lists:unzip([ infer_letfun1(Env, Clause) || Clause <- Clauses ]),
+    {_, Sigs = [Sig | _]} = lists:unzip(NameSigs),
+    _ = [ begin
+            ClauseT = typesig_to_fun_t(ClauseSig),
+            unify(Env, ClauseT, Type1, {check_typesig, Name, ClauseT, Type1})
+          end || ClauseSig <- Sigs ],
+    {{Name, Sig}, desugar_clauses(Ann, Fun, Sig, Clauses1)};
+infer_letfun(Env, LetFun = {letfun, Ann, Fun, _, _, _}) ->
+    {{Name, Sig}, Clause} = infer_letfun1(Env, LetFun),
+    {{Name, Sig}, desugar_clauses(Ann, Fun, Sig, [Clause])}.
+
+infer_letfun1(Env0, {letfun, Attrib, Fun = {id, NameAttrib, Name}, Args, What, Body}) ->
    Env = Env0#env{ stateful = aeso_syntax:get_ann(stateful, Attrib, false),
                    current_function = Fun },
-    check_unique_arg_names(Fun, Args),
-    ArgTypes  = [{ArgName, check_type(Env, arg_type(ArgAnn, T))} || {arg, ArgAnn, ArgName, T} <- Args],
+    {NewEnv, {typed, _, {tuple, _, TypedArgs}, {tuple_t, _, ArgTypes}}} = infer_pattern(Env, {tuple, [{origin, system} | NameAttrib], Args}),
    ExpectedType = check_type(Env, arg_type(NameAttrib, What)),
-    NewBody={typed, _, _, ResultType} = check_expr(bind_vars(ArgTypes, Env), Body, ExpectedType),
-    NewArgs = [{arg, A1, {id, A2, ArgName}, T}
-               || {{_, T}, {arg, A1, {id, A2, ArgName}, _}} <- lists:zip(ArgTypes, Args)],
+    NewBody={typed, _, _, ResultType} = check_expr(NewEnv, Body, ExpectedType),
    NamedArgs = [],
-    TypeSig = {type_sig, Attrib, none, NamedArgs, [T || {arg, _, _, T} <- NewArgs], ResultType},
+    TypeSig = {type_sig, Attrib, none, NamedArgs, ArgTypes, ResultType},
    {{Name, TypeSig},
-     {letfun, Attrib, {id, NameAttrib, Name}, NewArgs, ResultType, NewBody}}.
+     {letfun, Attrib, {id, NameAttrib, Name}, TypedArgs, ResultType, NewBody}}.

-check_unique_arg_names(Fun, Args) ->
-    Name = fun({arg, _, {id, _, X}, _}) -> X end,
-    Names = lists:map(Name, Args),
-    Dups = lists:usort(Names -- lists:usort(Names)),
-    [ type_error({repeated_arg, Fun, Arg}) || Arg <- Dups ],
-    ok.
+desugar_clauses(Ann, Fun, {type_sig, _, _, _, ArgTypes, RetType}, Clauses) ->
+    NeedDesugar =
+        case Clauses of
+            [{letfun, _, _, As, _, _}] -> lists:any(fun({typed, _, {id, _, _}, _}) -> false; (_) -> true end, As);
+            _                          -> true
+        end,
+    case NeedDesugar of
+        false -> [Clause] = Clauses, Clause;
+        true  ->
+            NoAnn = [{origin, system}],
+            Args = [ {typed, NoAnn, {id, NoAnn, "x#" ++ integer_to_list(I)}, Type}
+                     || {I, Type} <- indexed(1, ArgTypes) ],
+            Tuple = fun([X]) -> X;
+                       (As) -> {typed, NoAnn, {tuple, NoAnn, As}, {tuple_t, NoAnn, ArgTypes}}
+                    end,
+            {letfun, Ann, Fun, Args, RetType,
+             {typed, NoAnn,
+              {switch, NoAnn, Tuple(Args),
+                [ {'case', AnnC, Tuple(ArgsC), Body}
+                || {letfun, AnnC, _, ArgsC, _, Body} <- Clauses ]}, RetType}}
+    end.

 print_typesig({Name, TypeSig}) ->
    ?PRINT_TYPES("Inferred ~s : ~s\n", [Name, pp(TypeSig)]).
@@ -1053,9 +1146,9 @@ get_call_chains(Graph, Visited, Queue, Stop, Acc) ->
    end.

 check_expr(Env, Expr, Type) ->
-    E = {typed, _, _, Type1} = infer_expr(Env, Expr),
+    {typed, Ann, Expr1, Type1} = infer_expr(Env, Expr),
    unify(Env, Type1, Type, {check_expr, Expr, Type1, Type}),
-    E.
+    {typed, Ann, Expr1, Type}.  %% Keep the user-given type

 infer_expr(_Env, Body={bool, As, _}) ->
    {typed, As, Body, {id, As, "bool"}};
@@ -1080,7 +1173,7 @@ infer_expr(_Env, Body={oracle_query_id, As, _}) ->
 infer_expr(_Env, Body={contract_pubkey, As, _}) ->
    Con = fresh_uvar(As),
    constrain([#is_contract_constraint{ contract_t = Con,
-                                        context    = Body }]),
+                                        context    = {contract_literal, Body} }]),
    {typed, As, Body, Con};
 infer_expr(_Env, Body={id, As, "_"}) ->
    {typed, As, Body, fresh_uvar(As)};
@@ -1099,21 +1192,20 @@ infer_expr(Env, {list, As, Elems}) ->
    NewElems = [check_expr(Env, X, ElemType) || X <- Elems],
    {typed, As, {list, As, NewElems}, {app_t, As, {id, As, "list"}, [ElemType]}};
 infer_expr(Env, {list_comp, As, Yield, []}) ->
-    {typed, _, TypedYield, Type} = infer_expr(Env, Yield),
+    {typed, _, _, Type} = TypedYield = infer_expr(Env, Yield),
    {typed, As, {list_comp, As, TypedYield, []}, {app_t, As, {id, As, "list"}, [Type]}};
-infer_expr(Env, {list_comp, As, Yield, [{comprehension_bind, Arg, BExpr}|Rest]}) ->
-    BindVarType = fresh_uvar(As),
+infer_expr(Env, {list_comp, As, Yield, [{comprehension_bind, Pat, BExpr}|Rest]}) ->
    TypedBind = {typed, As2, _, TypeBExpr} = infer_expr(Env, BExpr),
+    {NewE, TypedPat = {typed, _, _, PatType}} = infer_pattern(Env, Pat),
    unify( Env
         , TypeBExpr
-         , {app_t, As, {id, As, "list"}, [BindVarType]}
-         , {list_comp, TypedBind, TypeBExpr, {app_t, As2, {id, As, "list"}, [BindVarType]}}),
-    NewE = bind_var(Arg, BindVarType, Env),
+         , {app_t, As, {id, As, "list"}, [PatType]}
+         , {list_comp, TypedBind, TypeBExpr, {app_t, As2, {id, As, "list"}, [PatType]}}),
    {typed, _, {list_comp, _, TypedYield, TypedRest}, ResType} =
        infer_expr(NewE, {list_comp, As, Yield, Rest}),
    { typed
    , As
-    , {list_comp, As, TypedYield, [{comprehension_bind, {typed, Arg, BindVarType}, TypedBind}|TypedRest]}
+    , {list_comp, As, TypedYield, [{comprehension_bind, TypedPat, TypedBind}|TypedRest]}
    , ResType};
 infer_expr(Env, {list_comp, AttrsL, Yield, [{comprehension_if, AttrsIF, Cond}|Rest]}) ->
    NewCond = check_expr(Env, Cond, {id, AttrsIF, "bool"}),
@@ -1123,8 +1215,8 @@ infer_expr(Env, {list_comp, AttrsL, Yield, [{comprehension_if, AttrsIF, Cond}|Re
    , AttrsL
    , {list_comp, AttrsL, TypedYield, [{comprehension_if, AttrsIF, NewCond}|TypedRest]}
    , ResType};
-infer_expr(Env, {list_comp, AsLC, Yield, [{letval, AsLV, Pattern, Type, E}|Rest]}) ->
-    NewE = {typed, _, _, PatType} = infer_expr(Env, {typed, AsLV, E, arg_type(AsLV, Type)}),
+infer_expr(Env, {list_comp, AsLC, Yield, [{letval, AsLV, Pattern, E}|Rest]}) ->
+    NewE = {typed, _, _, PatType} = infer_expr(Env, E),
    BlockType = fresh_uvar(AsLV),
    {'case', _, NewPattern, NewRest} =
        infer_case( Env
@@ -1136,7 +1228,7 @@ infer_expr(Env, {list_comp, AsLC, Yield, [{letval, AsLV, Pattern, Type, E}|Rest]
    {typed, _, {list_comp, _, TypedYield, TypedRest}, ResType} = NewRest,
    { typed
    , AsLC
-    , {list_comp, AsLC, TypedYield, [{letval, AsLV, NewPattern, Type, NewE}|TypedRest]}
+    , {list_comp, AsLC, TypedYield, [{letval, AsLV, NewPattern, NewE}|TypedRest]}
    , ResType
    };
 infer_expr(Env, {list_comp, AsLC, Yield, [Def={letfun, AsLF, _, _, _, _}|Rest]}) ->
@@ -1155,8 +1247,6 @@ infer_expr(Env, {typed, As, Body, Type}) ->
    {typed, _, NewBody, NewType} = check_expr(Env, Body, Type1),
    {typed, As, NewBody, NewType};
 infer_expr(Env, {app, Ann, Fun, Args0}) ->
-    %% TODO: fix parser to give proper annotation for normal applications!
-    FunAnn     = aeso_syntax:get_ann(Fun),
    NamedArgs  = [ Arg || Arg = {named_arg, _, _, _} <- Args0 ],
    Args       = Args0 -- NamedArgs,
    case aeso_syntax:get_ann(format, Ann) of
@@ -1165,15 +1255,15 @@ infer_expr(Env, {app, Ann, Fun, Args0}) ->
        prefix ->
            infer_op(Env, Ann, Fun, Args, fun infer_prefix/1);
        _ ->
-            NamedArgsVar = fresh_uvar(FunAnn),
+            NamedArgsVar = fresh_uvar(Ann),
            NamedArgs1 = [ infer_named_arg(Env, NamedArgsVar, Arg) || Arg <- NamedArgs ],
            %% TODO: named args constraints
            NewFun={typed, _, _, FunType} = infer_expr(Env, Fun),
            NewArgs = [infer_expr(Env, A) || A <- Args],
            ArgTypes = [T || {typed, _, _, T} <- NewArgs],
-            ResultType = fresh_uvar(FunAnn),
+            ResultType = fresh_uvar(Ann),
            unify(Env, FunType, {fun_t, [], NamedArgsVar, ArgTypes, ResultType}, {infer_app, Fun, Args, FunType, ArgTypes}),
-            {typed, FunAnn, {app, Ann, NewFun, NamedArgs1 ++ NewArgs}, dereference(ResultType)}
+            {typed, Ann, {app, Ann, NewFun, NamedArgs1 ++ NewArgs}, dereference(ResultType)}
    end;
 infer_expr(Env, {'if', Attrs, Cond, Then, Else}) ->
    NewCond = check_expr(Env, Cond, {id, Attrs, "bool"}),
@@ -1253,6 +1343,16 @@ infer_expr(Env, {block, Attrs, Stmts}) ->
    BlockType = fresh_uvar(Attrs),
    NewStmts = infer_block(Env, Attrs, Stmts, BlockType),
    {typed, Attrs, {block, Attrs, NewStmts}, BlockType};
+infer_expr(_Env, {record_or_map_error, Attrs, Fields}) ->
+    type_error({mixed_record_and_map, {record, Attrs, Fields}}),
+    Type = fresh_uvar(Attrs),
+    {typed, Attrs, {record, Attrs, []}, Type};
+infer_expr(Env, {record_or_map_error, Attrs, Expr, []}) ->
+    type_error({empty_record_or_map_update, {record, Attrs, Expr, []}}),
+    infer_expr(Env, Expr);
+infer_expr(Env, {record_or_map_error, Attrs, Expr, Fields}) ->
+    type_error({mixed_record_and_map, {record, Attrs, Expr, Fields}}),
+    infer_expr(Env, Expr);
 infer_expr(Env, {lam, Attrs, Args, Body}) ->
    ArgTypes = [fresh_uvar(As) || {arg, As, _, _} <- Args],
    ArgPatterns = [{typed, As, Pat, check_type(Env, T)} || {arg, As, Pat, T} <- Args],
@@ -1261,7 +1361,7 @@ infer_expr(Env, {lam, Attrs, Args, Body}) ->
        infer_case(Env, Attrs, {tuple, Attrs, ArgPatterns}, {tuple_t, Attrs, ArgTypes}, Body, ResultType),
    NewArgs = [{arg, As, NewPat, NewT} || {typed, As, NewPat, NewT} <- NewArgPatterns],
    {typed, Attrs, {lam, Attrs, NewArgs, NewBody}, {fun_t, Attrs, [], ArgTypes, ResultType}};
-infer_expr(Env, Let = {letval, Attrs, _, _, _}) ->
+infer_expr(Env, Let = {letval, Attrs, _, _}) ->
    type_error({missing_body_for_let, Attrs}),
    infer_expr(Env, {block, Attrs, [Let, abort_expr(Attrs, "missing body")]});
 infer_expr(Env, Let = {letfun, Attrs, _, _, _, _}) ->
@@ -1324,16 +1424,20 @@ infer_op(Env, As, Op, Args, InferOp) ->
    unify(Env, ArgTypes, OperandTypes, {infer_app, Op, Args, Inferred, ArgTypes}),
    {typed, As, {app, As, Op, TypedArgs}, ResultType}.

-infer_case(Env, Attrs, Pattern, ExprType, Branch, SwitchType) ->
+infer_pattern(Env, Pattern) ->
    Vars = free_vars(Pattern),
    Names = [N || {id, _, N} <- Vars, N /= "_"],
    case Names -- lists:usort(Names) of
        [] -> ok;
        Nonlinear -> type_error({non_linear_pattern, Pattern, lists:usort(Nonlinear)})
    end,
-    NewEnv = bind_vars([{Var, fresh_uvar(Ann)} || Var = {id, Ann, _} <- Vars], Env#env{ in_pattern = true }),
-    NewPattern = {typed, _, _, PatType} = infer_expr(NewEnv, Pattern),
-    NewBranch  = check_expr(NewEnv, Branch, SwitchType),
+    NewEnv = bind_vars([{Var, fresh_uvar(Ann1)} || Var = {id, Ann1, _} <- Vars], Env#env{ in_pattern = true }),
+    NewPattern = infer_expr(NewEnv, Pattern),
+    {NewEnv#env{ in_pattern = Env#env.in_pattern }, NewPattern}.
+
+infer_case(Env, Attrs, Pattern, ExprType, Branch, SwitchType) ->
+    {NewEnv, NewPattern = {typed, _, _, PatType}} = infer_pattern(Env, Pattern),
+    NewBranch  = check_expr(NewEnv#env{ in_pattern = false }, Branch, SwitchType),
    unify(Env, PatType, ExprType, {case_pat, Pattern, PatType, ExprType}),
    {'case', Attrs, NewPattern, NewBranch}.

@@ -1347,11 +1451,11 @@ infer_block(Env, Attrs, [Def={letfun, Ann, _, _, _, _}|Rest], BlockType) ->
    FunT = typesig_to_fun_t(TypeSig),
    NewE = bind_var({id, Ann, Name}, FunT, Env),
    [LetFun|infer_block(NewE, Attrs, Rest, BlockType)];
-infer_block(Env, _, [{letval, Attrs, Pattern, Type, E}|Rest], BlockType) ->
-    NewE = {typed, _, _, PatType} = infer_expr(Env, {typed, Attrs, E, arg_type(aeso_syntax:get_ann(Pattern), Type)}),
+infer_block(Env, _, [{letval, Attrs, Pattern, E}|Rest], BlockType) ->
+    NewE = {typed, _, _, PatType} = infer_expr(Env, E),
    {'case', _, NewPattern, {typed, _, {block, _, NewRest}, _}} =
        infer_case(Env, Attrs, Pattern, PatType, {block, Attrs, Rest}, BlockType),
-    [{letval, Attrs, NewPattern, Type, NewE}|NewRest];
+    [{letval, Attrs, NewPattern, NewE}|NewRest];
 infer_block(Env, Attrs, [E|Rest], BlockType) ->
    [infer_expr(Env, E)|infer_block(Env, Attrs, Rest, BlockType)].

@@ -1393,18 +1497,13 @@ infer_prefix({IntOp,As}) when IntOp =:= '-' ->
 abort_expr(Ann, Str) ->
    {app, Ann, {id, Ann, "abort"}, [{string, Ann, Str}]}.

-free_vars({int, _, _}) ->
-    [];
-free_vars({char, _, _}) ->
-    [];
-free_vars({string, _, _}) ->
-    [];
-free_vars({bool, _, _}) ->
-    [];
-free_vars(Id={id, _, _}) ->
-    [Id];
-free_vars({con, _, _}) ->
-    [];
+free_vars({int, _, _})    -> [];
+free_vars({char, _, _})   -> [];
+free_vars({string, _, _}) -> [];
+free_vars({bool, _, _})   -> [];
+free_vars(Id={id, _, _})  -> [Id];
+free_vars({con, _, _})    -> [];
+free_vars({qcon, _, _})   -> [];
 free_vars({tuple, _, Cpts}) ->
    free_vars(Cpts);
 free_vars({list, _, Elems}) ->
@@ -1413,6 +1512,8 @@ free_vars({app, _, {'::', _}, Args}) ->
    free_vars(Args);
 free_vars({app, _, {con, _, _}, Args}) ->
    free_vars(Args);
+free_vars({app, _, {qcon, _, _}, Args}) ->
+    free_vars(Args);
 free_vars({record, _, Fields}) ->
    free_vars([E || {field, _, _, E} <- Fields]);
 free_vars({typed, _, A, _}) ->
@@ -1654,11 +1755,11 @@ check_record_create_constraints(Env, [C | Cs]) ->

 check_is_contract_constraints(_Env, []) -> ok;
 check_is_contract_constraints(Env, [C | Cs]) ->
-    #is_contract_constraint{ contract_t = Type, context = Lit } = C,
+    #is_contract_constraint{ contract_t = Type, context = Cxt } = C,
    Type1 = unfold_types_in_type(Env, instantiate(Type)),
    case lookup_type(Env, record_type_name(Type1)) of
        {_, {_Ann, {[], {contract_t, _}}}} -> ok;
-        _ -> type_error({not_a_contract_type, Type1, Lit})
+        _ -> type_error({not_a_contract_type, Type1, Cxt})
    end,
    check_is_contract_constraints(Env, Cs).

@@ -1748,7 +1849,7 @@ solve_known_record_types(Env, Constraints) ->
                             C
                     end;
                _ ->
-                    type_error({not_a_record_type, RecType, When}),
+                    type_error({not_a_record_type, instantiate(RecType), When}),
                    not_solved
             end
         end
@@ -2079,6 +2180,9 @@ freshen_type_sig(Ann, TypeSig = {type_sig, _, Constr, _, _, _}) ->
    FunT.

 apply_typesig_constraint(_Ann, none, _FunT) -> ok;
+apply_typesig_constraint(Ann, address_to_contract, {fun_t, _, [], [_], Type}) ->
+    constrain([#is_contract_constraint{ contract_t = Type,
+                                        context    = {address_to_contract, Ann}}]);
 apply_typesig_constraint(Ann, bytes_concat, {fun_t, _, [], [A, B], C}) ->
    add_bytes_constraint({add_bytes, Ann, concat, A, B, C});
 apply_typesig_constraint(Ann, bytes_split, {fun_t, _, [], [C], {tuple_t, _, [A, B]}}) ->
@@ -2177,12 +2281,28 @@ mk_error({not_a_record_type, Type, Why}) ->
    Msg = io_lib:format("~s\n", [pp_type("Not a record type: ", Type)]),
    {Pos, Ctxt} = pp_why_record(Why),
    mk_t_err(Pos, Msg, Ctxt);
-mk_error({not_a_contract_type, Type, Lit}) ->
-    Msg = io_lib:format("The type ~s is not a contract type\n"
-                        "when checking that the contract literal at ~s\n~s\n"
+mk_error({not_a_contract_type, Type, Cxt}) ->
+    Msg =
+        case Type of
+            {tvar, _, _} ->
+                "Unresolved contract type\n";
+            _ ->
+                io_lib:format("The type ~s is not a contract type\n", [pp_type("", Type)])
+        end,
+    {Pos, Cxt1} =
+        case Cxt of
+            {contract_literal, Lit} ->
+                {pos(Lit),
+                 io_lib:format("when checking that the contract literal\n~s\n"
                               "has the type\n~s\n",
-                        [pp_type("", Type), pp_loc(Lit), pp_expr("  ", Lit), pp_type("  ", Type)]),
-    mk_t_err(pos(Lit), Msg);
+                               [pp_expr("  ", Lit), pp_type("  ", Type)])};
+            {address_to_contract, Ann} ->
+                {pos(Ann),
+                 io_lib:format("when checking that the call to\n  Address.to_contract\n"
+                               "has the type\n~s\n",
+                               [pp_type("  ", Type)])}
+        end,
+    mk_t_err(Pos, Msg, Cxt1);
 mk_error({non_linear_pattern, Pattern, Nonlinear}) ->
    Msg = io_lib:format("Repeated name~s ~s in pattern\n~s (at ~s)\n",
                        [plural("", "s", Nonlinear), string:join(Nonlinear, ", "),
@@ -2344,6 +2464,10 @@ mk_error({contract_has_no_entrypoints, Con}) ->
                        "contract functions must be declared with the 'entrypoint' keyword instead of\n"
                        "'function'.\n", [pp_expr("", Con), pp_loc(Con)]),
    mk_t_err(pos(Con), Msg);
+mk_error({definition_in_non_main_contract, Ann, {id, _, Id}}) ->
+    Msg = "Only the main contract can contain defined functions or entrypoints.\n",
+    Cxt = io_lib:format("Fix: replace the definition of '~s' by a type signature.\n", [Id]),
+    mk_t_err(pos(Ann), Msg, Cxt);
 mk_error({unbound_type, Type}) ->
    Msg = io_lib:format("Unbound type ~s (at ~s).\n", [pp_type("", Type), pp_loc(Type)]),
    mk_t_err(pos(Type), Msg);
@@ -2359,6 +2483,10 @@ mk_error({cannot_call_init_function, Ann}) ->
    Msg = "The 'init' function is called exclusively by the create contract transaction\n"
          "and cannot be called from the contract code.\n",
    mk_t_err(pos(Ann), Msg);
+mk_error({contract_treated_as_namespace, Ann, [Con, Fun] = QName}) ->
+    Msg = io_lib:format("Invalid call to contract entrypoint '~s'.\n", [string:join(QName, ".")]),
+    Cxt = io_lib:format("It must be called as 'c.~s' for some c : ~s.\n", [Fun, Con]),
+    mk_t_err(pos(Ann), Msg, Cxt);
 mk_error({bad_top_level_decl, Decl}) ->
    What = case element(1, Decl) of
               letval -> "function or entrypoint";
@@ -2383,6 +2511,23 @@ mk_error({unsolved_bytes_constraint, Ann, split, A, B, C}) ->
                        [ pp_type("  - ", C), pp_loc(C), pp_type("  - ", A), pp_loc(A),
                          pp_type("  - ", B), pp_loc(B)]),
    mk_t_err(pos(Ann), Msg);
+mk_error({failed_to_get_compiler_version, Err}) ->
+    Msg = io_lib:format("Failed to get compiler version. Error:\n  ~p\n", [Err]),
+    mk_t_err(pos(0, 0), Msg);
+mk_error({compiler_version_mismatch, Ann, Version, Op, Bound}) ->
+    PrintV = fun(V) -> string:join([integer_to_list(N) || N <- V], ".") end,
+    Msg = io_lib:format("Cannot compile with this version of the compiler,\n"
+                        "because it does not satisfy the constraint"
+                        " ~s ~s ~s\n", [PrintV(Version), Op, PrintV(Bound)]),
+    mk_t_err(pos(Ann), Msg);
+mk_error({empty_record_or_map_update, Expr}) ->
+    Msg = io_lib:format("Empty record/map update\n~s",
+                        [pp_expr("  ", Expr)]),
+    mk_t_err(pos(Expr), Msg);
+mk_error({mixed_record_and_map, Expr}) ->
+    Msg = io_lib:format("Mixed record fields and map keys in\n~s",
+                        [pp_expr("  ", Expr)]),
+    mk_t_err(pos(Expr), Msg);
 mk_error(Err) ->
    Msg = io_lib:format("Unknown error: ~p\n", [Err]),
    mk_t_err(pos(0, 0), Msg).
@@ -2660,3 +2805,7 @@ updates_key(Name, Updates) ->
    Updates1 = [ Upd  || {Upd, false, _} <- Xs ],
    More     = [ Rest || {_, true, Rest} <- Xs ],
    {More, Updates1}.
+
+indexed(I, Xs) ->
+    lists:zip(lists:seq(I, I + length(Xs) - 1), Xs).
+
@@ -24,6 +24,8 @@
 -type var_name() :: string().
 -type sophia_name() :: [string()].

+-type state_reg() :: pos_integer().
+
 -type builtin() :: atom().

 -type op() :: '+' | '-' | '*' | '/' | mod | '^' | '++' | '::' |
@@ -32,7 +34,7 @@
              map_delete | map_member | map_size | string_length |
              string_concat | bits_set | bits_clear | bits_test | bits_sum |
              bits_intersection | bits_union | bits_difference |
-              contract_to_address | crypto_verify_sig | crypto_verify_sig_secp256k1 |
+              contract_to_address | address_to_contract | crypto_verify_sig | crypto_verify_sig_secp256k1 |
              crypto_sha3 | crypto_sha256 | crypto_blake2b |
              crypto_ecverify_secp256k1 | crypto_ecrecover_secp256k1.

@@ -61,6 +63,8 @@
               | {funcall, fexpr(), [fexpr()]}  %% Call to unknown function
               | {closure, fun_name(), fexpr()}
               | {switch, fsplit()}
+               | {set_state, state_reg(), fexpr()}
+               | {get_state, state_reg()}
               %% The following (unapplied top-level functions/builtins and
               %% lambdas) are generated by the fcode compiler, but translated
               %% to closures by the lambda lifter.
@@ -109,6 +113,7 @@

 -type fcode() :: #{ contract_name := string(),
                    state_type    := ftype(),
+                    state_layout  := state_layout(),
                    event_type    := ftype() | none,
                    functions     := #{ fun_name() => fun_def() },
                    payable       := boolean() }.
@@ -130,12 +135,15 @@
                 | {namespace, string()}
                 | {abstract_contract, string()}.

+-type state_layout() :: {tuple, [state_layout()]} | {reg, state_reg()}.
+
 -type env() :: #{ type_env     := type_env(),
                  fun_env      := fun_env(),
                  con_env      := con_env(),
                  event_type   => aeso_syntax:typedef(),
                  builtins     := builtins(),
                  options      := [option()],
+                  state_layout => state_layout(),
                  context      => context(),
                  vars         => [var_name()],
                  functions    := #{ fun_name() => fun_def() } }.
@@ -149,12 +157,14 @@
 -spec ast_to_fcode(aeso_syntax:ast(), [option()]) -> fcode().
 ast_to_fcode(Code, Options) ->
    Verbose = lists:member(pp_fcode, Options),
+    init_fresh_names(),
    FCode1 = to_fcode(init_env(Options), Code),
    [io:format("-- Before lambda lifting --\n~s\n\n", [format_fcode(FCode1)]) || Verbose],
-    FCode2 = lambda_lift(FCode1),
-    [ io:format("-- After lambda lifting --\n~s\n\n", [format_fcode(FCode2)]) || Verbose, FCode2 /= FCode1 ],
-    FCode3 = optimize_fcode(FCode2),
-    [ io:format("-- After optimization --\n~s\n\n", [format_fcode(FCode3)]) || Verbose, FCode3 /= FCode2 ],
+    FCode2 = optimize_fcode(FCode1),
+    [ io:format("-- After optimization --\n~s\n\n", [format_fcode(FCode2)]) || Verbose, FCode2 /= FCode1 ],
+    FCode3 = lambda_lift(FCode2),
+    [ io:format("-- After lambda lifting --\n~s\n\n", [format_fcode(FCode3)]) || Verbose, FCode3 /= FCode2 ],
+    clear_fresh_names(),
    FCode3.

 %% -- Environment ------------------------------------------------------------
@@ -200,12 +210,14 @@ builtins() ->
                              {"union", 2}, {"difference", 2}, {"none", none}, {"all", none}]},
              {["Bytes"],    [{"to_int", 1}, {"to_str", 1}, {"concat", 2}, {"split", 1}]},
              {["Int"],      [{"to_str", 1}]},
-              {["Address"],  [{"to_str", 1}, {"is_oracle", 1}, {"is_contract", 1}, {"is_payable", 1}]}
+              {["Address"],  [{"to_str", 1}, {"to_contract", 1}, {"is_oracle", 1}, {"is_contract", 1}, {"is_payable", 1}]}
             ],
    maps:from_list([ {NS ++ [Fun], {MkName(NS, Fun), Arity}}
                     || {NS, Funs} <- Scopes,
                        {Fun, Arity} <- Funs ]).

+state_layout(Env) -> maps:get(state_layout, Env, {reg, 1}).
+
 -define(type(T),       fun([])     -> T end).
 -define(type(X, T),    fun([X])    -> T end).
 -define(type(X, Y, T), fun([X, Y]) -> T end).
@@ -221,7 +233,7 @@ init_type_env() ->
       ["hash"]         => ?type(hash),
       ["signature"]    => ?type(signature),
       ["oracle"]       => ?type(Q, R, {oracle, Q, R}),
-       ["oracle_query"] => ?type(_, _, oracle_query),    %% TODO: not in Fate
+       ["oracle_query"] => ?type(_, _, oracle_query),
       ["list"]         => ?type(T, {list, T}),
       ["map"]          => ?type(K, V, {map, K, V}),
       ["option"]       => ?type(T, {variant, [[], [T]]}),
@@ -229,7 +241,13 @@ init_type_env() ->
     }.

 is_no_code(Env) ->
-    proplists:get_value(no_code, maps:get(options, Env, []), false).
+    get_option(no_code, Env).
+
+get_option(Opt, Env) ->
+    get_option(Opt, Env, false).
+
+get_option(Opt, Env, Default) ->
+    proplists:get_value(Opt, maps:get(options, Env, []), Default).

 %% -- Compilation ------------------------------------------------------------

@@ -244,9 +262,11 @@ to_fcode(Env, [{contract, Attrs, MainCon = {con, _, Main}, Decls}]) ->
        decls_to_fcode(MainEnv, Decls),
    StateType   = lookup_type(Env1, [Main, "state"], [], {tuple, []}),
    EventType   = lookup_type(Env1, [Main, "event"], [], none),
+    StateLayout = state_layout(Env1),
    Payable     = proplists:get_value(payable, Attrs, false),
    #{ contract_name => Main,
       state_type    => StateType,
+       state_layout  => StateLayout,
       event_type    => EventType,
       payable       => Payable,
       functions     => add_init_function(Env1, MainCon, StateType,
@@ -266,9 +286,7 @@ decls_to_fcode(Env, Decls) ->
    %% environment.
    Env1 = add_fun_env(Env, Decls),
    lists:foldl(fun(D, E) ->
-                    init_fresh_names(),
                    R = decl_to_fcode(E, D),
-                    clear_fresh_names(),
                    R
                end, Env1, Decls).

@@ -304,14 +322,15 @@ typedef_to_fcode(Env, Id = {id, _, Name}, Xs, Def) ->
    FDef = fun(Args) when length(Args) == length(Xs) ->
                Sub = maps:from_list(lists:zip([X || {tvar, _, X} <- Xs], Args)),
                case Def of
-                    {record_t, Fields} -> {todo, Xs, Args, record_t, Fields};
+                    {record_t, Fields} ->
+                        {tuple, [type_to_fcode(Env, Sub, T) || {field_t, _, _, T} <- Fields]};
                    {variant_t, Cons}  ->
                        FCons = [ begin
                                      {constr_t, _, _, Ts} = Con,
                                      [type_to_fcode(Env, Sub, T) || T <- Ts]
                                  end || Con <- Cons ],
                        {variant, FCons};
-                    {alias_t, Type}    -> {todo, Xs, Args, alias_t, Type}
+                    {alias_t, Type}    -> type_to_fcode(Env, Sub, Type)
                end;
              (Args) -> internal_error({type_arity_mismatch, Name, length(Args), length(Xs)})
           end,
@@ -333,7 +352,34 @@ typedef_to_fcode(Env, Id = {id, _, Name}, Xs, Def) ->
             "event" -> Env1#{ event_type => Def };
             _       -> Env1
           end,
-    bind_type(Env2, Q, FDef).
+    Env3 = compute_state_layout(Env2, Name, FDef),
+    bind_type(Env3, Q, FDef).
+
+compute_state_layout(Env = #{ context := {main_contract, _} }, "state", Type) ->
+    NoLayout = get_option(no_flatten_state, Env),
+    Layout =
+        case Type([]) of
+            _ when NoLayout -> {reg, 1};
+            T ->
+                {_, L} = compute_state_layout(1, T),
+                L
+        end,
+    Env#{ state_layout => Layout };
+compute_state_layout(Env, _, _) -> Env.
+
+compute_state_layout(R, {tuple, [T]}) ->
+    compute_state_layout(R, T);
+compute_state_layout(R, {tuple, Ts}) ->
+    {R1, Ls} = compute_state_layout(R, Ts),
+    {R1, {tuple, Ls}};
+compute_state_layout(R, []) ->
+    {R, []};
+compute_state_layout(R, [H | T]) ->
+    {R1, H1} = compute_state_layout(R, H),
+    {R2, T1} = compute_state_layout(R1, T),
+    {R2, [H1 | T1]};
+compute_state_layout(R, _) ->
+    {R + 1, {reg, R}}.

 check_state_and_event_types(#{ context := {main_contract, _} }, Id, [_ | _]) ->
    case Id of
@@ -369,9 +415,12 @@ type_to_fcode(Env, Sub, {fun_t, _, Named, Args, Res}) ->
 type_to_fcode(_Env, _Sub, Type) ->
    error({todo, Type}).

-spec args_to_fcode(env(), [aeso_syntax:arg()]) -> [{var_name(), ftype()}].
+-spec args_to_fcode(env(), [aeso_syntax:pat()]) -> [{var_name(), ftype()}].
 args_to_fcode(Env, Args) ->
-    [ {Name, type_to_fcode(Env, Type)} || {arg, _, {id, _, Name}, Type} <- Args ].
+    [ case Arg of
+          {id, _, Name} -> {Name, type_to_fcode(Env, Type)};
+          _ -> internal_error({bad_arg, Arg})   %% Pattern matching has been moved to the rhs at this point
+      end || {typed, _, Arg, Type} <- Args ].

 -define(make_let(X, Expr, Body),
        make_let(Expr, fun(X) -> Body end)).
@@ -386,6 +435,13 @@ make_let(Expr, Body) ->
            {'let', X, Expr, Body({var, X})}
    end.

+let_bind(X, {var, Y}, Body) -> rename([{X, Y}], Body);
+let_bind(X, Expr, Body)     -> {'let', X, Expr, Body}.
+
+let_bind(Binds, Body) ->
+    lists:foldr(fun({X, E}, Rest) -> let_bind(X, E, Rest) end,
+                Body, Binds).
+
 -spec expr_to_fcode(env(), aeso_syntax:expr()) -> fexpr().
 expr_to_fcode(Env, {typed, _, Expr, Type}) ->
    expr_to_fcode(Env, Type, Expr);
@@ -446,7 +502,7 @@ expr_to_fcode(Env, _Type, {app, _, {typed, _, {C, _, _} = Con, _}, Args}) when C

 %% Tuples
 expr_to_fcode(Env, _Type, {tuple, _, Es}) ->
-    {tuple, [expr_to_fcode(Env, E) || E <- Es]};
+    make_tuple([expr_to_fcode(Env, E) || E <- Es]);

 %% Records
 expr_to_fcode(Env, Type, {proj, _Ann, Rec = {typed, _, _, RecType}, {id, _, X}}) ->
@@ -458,18 +514,28 @@ expr_to_fcode(Env, Type, {proj, _Ann, Rec = {typed, _, _, RecType}, {id, _, X}})
            FArgs = [type_to_fcode(Env, Arg) || Arg <- Args],
            {remote_u, FArgs, type_to_fcode(Env, Ret), expr_to_fcode(Env, Rec),
                       {entrypoint, list_to_binary(X)}};
+        {record_t, [_]} -> expr_to_fcode(Env, Rec); %% Singleton record
        {record_t, _} ->
            {proj, expr_to_fcode(Env, Rec), field_index(Rec, X)}
    end;

+expr_to_fcode(Env, {record_t, [FieldT]}, {record, _Ann, [_] = Fields}) ->
+    {set, E} = field_value(FieldT, Fields),
+    expr_to_fcode(Env, E);
 expr_to_fcode(Env, {record_t, FieldTypes}, {record, _Ann, Fields}) ->
    FVal = fun(F) ->
             %% All fields are present and no updates
             {set, E} = field_value(F, Fields),
             expr_to_fcode(Env, E)
           end,
-    {tuple, lists:map(FVal, FieldTypes)};
+    make_tuple(lists:map(FVal, FieldTypes));

+expr_to_fcode(Env, {record_t, [FieldT]}, {record, _Ann, Rec, Fields}) ->
+    case field_value(FieldT, Fields) of
+        false       -> expr_to_fcode(Env, Rec);
+        {set, E}    -> expr_to_fcode(Env, E);
+        {upd, Z, E} -> {'let', Z, expr_to_fcode(Env, Rec), expr_to_fcode(bind_var(Env, Z), E)}
+    end;
 expr_to_fcode(Env, {record_t, FieldTypes}, {record, _Ann, Rec, Fields}) ->
    X    = fresh_name(),
    Proj = fun(I) -> {proj, {var, X}, I - 1} end,
@@ -501,9 +567,12 @@ expr_to_fcode(Env, _Type, {app, _, {'..', _}, [A, B]}) ->

 expr_to_fcode(Env, _Type, {list_comp, _, Yield, []}) ->
    {op, '::', [expr_to_fcode(Env, Yield), nil]};
-expr_to_fcode(Env, _Type, {list_comp, As, Yield, [{comprehension_bind, {typed, {id, _, Arg}, _}, BindExpr}|Rest]}) ->
+expr_to_fcode(Env, _Type, {list_comp, As, Yield, [{comprehension_bind, Pat = {typed, _, _, PatType}, BindExpr}|Rest]}) ->
+    Arg  = fresh_name(),
    Env1 = bind_var(Env, Arg),
-    Bind = {lam, [Arg], expr_to_fcode(Env1, {list_comp, As, Yield, Rest})},
+    Bind = {lam, [Arg], expr_to_fcode(Env1, {switch, As, {typed, As, {id, As, Arg}, PatType},
+                                                [{'case', As, Pat, {list_comp, As, Yield, Rest}},
+                                                 {'case', As, {id, As, "_"}, {list, As, []}}]})},
    {def_u, FlatMap, _} = resolve_fun(Env, ["ListInternal", "flat_map"]),
    {def, FlatMap, [Bind, expr_to_fcode(Env, BindExpr)]};
 expr_to_fcode(Env, Type, {list_comp, As, Yield, [{comprehension_if, _, Cond}|Rest]}) ->
@@ -511,7 +580,7 @@ expr_to_fcode(Env, Type, {list_comp, As, Yield, [{comprehension_if, _, Cond}|Res
            expr_to_fcode(Env, Type, {list_comp, As, Yield, Rest}),
            nil
           );
-expr_to_fcode(Env, Type, {list_comp, As, Yield, [LV = {letval, _, _, _, _}|Rest]}) ->
+expr_to_fcode(Env, Type, {list_comp, As, Yield, [LV = {letval, _, _, _}|Rest]}) ->
    expr_to_fcode(Env, Type, {block, As, [LV, {list_comp, As, Yield, Rest}]});
 expr_to_fcode(Env, Type, {list_comp, As, Yield, [LF = {letfun, _, _, _, _, _}|Rest]}) ->
    expr_to_fcode(Env, Type, {block, As, [LF, {list_comp, As, Yield, Rest}]});
@@ -556,8 +625,8 @@ expr_to_fcode(Env, _Type, {app, _, Fun = {typed, _, _, {fun_t, _, NamedArgsT, _,
    Args1 = get_named_args(NamedArgsT, Args),
    FArgs = [expr_to_fcode(Env, Arg) || Arg <- Args1],
    case expr_to_fcode(Env, Fun) of
-        {builtin_u, B, _Ar, TypeArgs}     -> builtin_to_fcode(B, FArgs ++ TypeArgs);
-        {builtin_u, B, _Ar}               -> builtin_to_fcode(B, FArgs);
+        {builtin_u, B, _Ar, TypeArgs}     -> builtin_to_fcode(state_layout(Env), B, FArgs ++ TypeArgs);
+        {builtin_u, B, _Ar}               -> builtin_to_fcode(state_layout(Env), B, FArgs);
        {def_u, F, _Ar}                   -> {def, F, FArgs};
        {remote_u, ArgsT, RetT, Ct, RFun} -> {remote, ArgsT, RetT, Ct, RFun, FArgs};
        FFun ->
@@ -621,6 +690,13 @@ make_if(Cond, Then, Else) ->
    X = fresh_name(),
    {'let', X, Cond, make_if({var, X}, Then, Else)}.

+-spec make_tuple([fexpr()]) -> fexpr().
+make_tuple([E]) -> E;
+make_tuple(Es) -> {tuple, Es}.
+
+-spec strip_singleton_tuples(ftype()) -> ftype().
+strip_singleton_tuples({tuple, [T]}) -> strip_singleton_tuples(T);
+strip_singleton_tuples(T) -> T.

 get_oracle_type(oracle_register,     {fun_t, _, _, _, OType})       -> OType;
 get_oracle_type(oracle_query,        {fun_t, _, _, [OType | _], _}) -> OType;
@@ -649,7 +725,7 @@ validate_aens_resolve_type(Ann, {app_t, _, _, [Type]}, {variant, [[], [FType]]})

 ensure_first_order_entrypoint(Ann, Id = {id, _, Name}, Args, Ret, FArgs, FRet) ->
    [ ensure_first_order(FT, {invalid_entrypoint, higher_order, Ann1, Id, {argument, X, T}})
-      || {{arg, Ann1, X, T}, {_, FT}} <- lists:zip(Args, FArgs) ],
+      || {{typed, Ann1, X, T}, {_, FT}} <- lists:zip(Args, FArgs) ],
    [ ensure_first_order(FRet, {invalid_entrypoint, higher_order, Ann, Id, {result, Ret}})
      || Name /= "init" ],  %% init can return higher-order values, since they're written to the store
                            %% rather than being returned.
@@ -708,10 +784,13 @@ split_tree(Env, Vars, Alts = [{'case', Pats, Body} | _]) ->
            {nosplit, rename(Ren, Body)};
        I when is_integer(I) ->
            {Vars0, [{X, Type} | Vars1]} = lists:split(I - 1, Vars),
+            Type1 = strip_singleton_tuples(Type),
            SAlts = merge_alts(I, X, [ split_alt(I, A) || A <- Alts ]),
-            Cases = [ {'case', SPat, split_tree(Env, Vars0 ++ split_vars(SPat, Type) ++ Vars1, FAlts)}
+            MakeCase = fun({var, Z}, Split) -> {'case', {var, "_"}, rename_split([{Z, X}], Split)};
+                          (SPat, Split)     -> {'case', SPat, Split} end,
+            Cases = [ MakeCase(SPat, split_tree(Env, Vars0 ++ split_vars(SPat, Type1) ++ Vars1, FAlts))
                      || {SPat, FAlts} <- SAlts ],
-            {split, Type, X, Cases}
+            {split, Type1, X, Cases}
    end.

 -spec merge_alts(integer(), var_name(), [{fsplit_pat(), falt()}]) -> [{fsplit_pat(), [falt()]}].
@@ -834,7 +913,7 @@ pat_to_fcode(Env, _Type, {app, _, {typed, _, {C, _, _} = Con, _}, Pats}) when C
    #con_tag{tag = I, arities = As} = lookup_con(Env, Con),
    {con, As, I, [pat_to_fcode(Env, Pat) || Pat <- Pats]};
 pat_to_fcode(Env, _Type, {tuple, _, Pats}) ->
-    {tuple, [ pat_to_fcode(Env, Pat) || Pat <- Pats ]};
+    make_tuple([ pat_to_fcode(Env, Pat) || Pat <- Pats ]);
 pat_to_fcode(_Env, _Type, {bool, _, B})   -> {bool, B};
 pat_to_fcode(_Env, _Type, {int, _, N})    -> {int, N};
 pat_to_fcode(_Env, _Type, {char, _, N})   -> {int, N};
@@ -852,8 +931,8 @@ pat_to_fcode(Env, {record_t, Fields}, {record, _, FieldPats}) ->
                        {set, Pat} -> Pat
                        %% {upd, _, _} is impossible in patterns
                    end end,
-    {tuple, [pat_to_fcode(Env, FieldPat(Field))
-             || Field <- Fields]};
+    make_tuple([pat_to_fcode(Env, FieldPat(Field))
+                || Field <- Fields]);

 pat_to_fcode(_Env, Type, Pat) ->
    error({todo, Pat, ':', Type}).
@@ -887,10 +966,16 @@ decision_tree_to_fcode({'if', A, Then, Else}) ->
 %% -- Statements --

 -spec stmts_to_fcode(env(), [aeso_syntax:stmt()]) -> fexpr().
-stmts_to_fcode(Env, [{letval, _, {typed, _, {id, _, X}, _}, _, Expr} | Stmts]) ->
+stmts_to_fcode(Env, [{letval, _, {typed, _, {id, _, X}, _}, Expr} | Stmts]) ->
    {'let', X, expr_to_fcode(Env, Expr), stmts_to_fcode(bind_var(Env, X), Stmts)};
+stmts_to_fcode(Env, [{letval, Ann, Pat, Expr} | Stmts]) ->
+    expr_to_fcode(Env, {switch, Ann, Expr, [{'case', Ann, Pat, {block, Ann, Stmts}}]});
 stmts_to_fcode(Env, [{letfun, Ann, {id, _, X}, Args, _Type, Expr} | Stmts]) ->
-    {'let', X, expr_to_fcode(Env, {lam, Ann, Args, Expr}),
+    LamArgs = [ case Arg of
+                    {typed, Ann1, Id, T} -> {arg, Ann1, Id, T};
+                    _ -> internal_error({bad_arg, Arg})   %% pattern matching has been desugared
+                end || Arg <- Args ],
+    {'let', X, expr_to_fcode(Env, {lam, Ann, LamArgs, Expr}),
               stmts_to_fcode(bind_var(Env, X), Stmts)};
 stmts_to_fcode(Env, [Expr]) ->
    expr_to_fcode(Env, Expr);
@@ -904,27 +989,45 @@ op_builtins() ->
     string_length, string_concat, string_sha3, string_sha256, string_blake2b,
     bits_set, bits_clear, bits_test, bits_sum, bits_intersection, bits_union,
     bits_difference, int_to_str, address_to_str, crypto_verify_sig,
+     address_to_contract,
     crypto_verify_sig_secp256k1, crypto_sha3, crypto_sha256, crypto_blake2b,
     crypto_ecverify_secp256k1, crypto_ecrecover_secp256k1
    ].

-builtin_to_fcode(require, [Cond, Msg]) ->
+set_state({reg, R}, Val) ->
+    {set_state, R, Val};
+set_state({tuple, Ls}, Val) ->
+    ?make_let(X, Val,
+    lists:foldr(fun({I, L}, Code) ->
+                    {'let', "_", set_state(L, {proj, X, I - 1}), Code}
+                end, {tuple, []}, indexed(Ls))).
+
+get_state({reg, R}) ->
+    {get_state, R};
+get_state({tuple, Ls}) ->
+    {tuple, [get_state(L) || L <- Ls]}.
+
+builtin_to_fcode(Layout, set_state, [Val]) ->
+    set_state(Layout, Val);
+builtin_to_fcode(Layout, get_state, []) ->
+    get_state(Layout);
+builtin_to_fcode(_Layout, require, [Cond, Msg]) ->
    make_if(Cond, {tuple, []}, {builtin, abort, [Msg]});
-builtin_to_fcode(chain_event, [Event]) ->
+builtin_to_fcode(_Layout, chain_event, [Event]) ->
    {def, event, [Event]};
-builtin_to_fcode(map_delete, [Key, Map]) ->
+builtin_to_fcode(_Layout, map_delete, [Key, Map]) ->
    {op, map_delete, [Map, Key]};
-builtin_to_fcode(map_member, [Key, Map]) ->
+builtin_to_fcode(_Layout, map_member, [Key, Map]) ->
    {op, map_member, [Map, Key]};
-builtin_to_fcode(map_lookup, [Key0, Map0]) ->
+builtin_to_fcode(_Layout, map_lookup, [Key0, Map0]) ->
    ?make_let(Key, Key0,
    ?make_let(Map, Map0,
     make_if({op, map_member, [Map, Key]},
             {con, [0, 1], 1, [{op, map_get, [Map, Key]}]},
             {con, [0, 1], 0, []})));
-builtin_to_fcode(map_lookup_default, [Key, Map, Def]) ->
+builtin_to_fcode(_Layout, map_lookup_default, [Key, Map, Def]) ->
    {op, map_get_d, [Map, Key, Def]};
-builtin_to_fcode(Builtin, Args) ->
+builtin_to_fcode(_Layout, Builtin, Args) ->
    case lists:member(Builtin, op_builtins()) of
        true  -> {op, Builtin, Args};
        false -> {builtin, Builtin, Args}
@@ -939,8 +1042,9 @@ add_init_function(Env, Main, StateType, Funs0) ->
            Funs     = add_default_init_function(Env, Main, StateType, Funs0),
            InitName = {entrypoint, <<"init">>},
            InitFun  = #{ body := InitBody} = maps:get(InitName, Funs),
-            Funs#{ InitName => InitFun#{ return => {tuple, []},
-                                         body   => {builtin, set_state, [InitBody]} } }
+            Funs1 = Funs#{ InitName => InitFun#{ return => {tuple, []},
+                                                 body   => builtin_to_fcode(state_layout(Env), set_state, [InitBody]) } },
+            Funs1
    end.

 add_default_init_function(_Env, Main, StateType, Funs) ->
@@ -991,12 +1095,10 @@ event_function(_Env = #{event_type := {variant_t, EventCons}}, EventType = {vari
 %% the top-level and replace it with a closure.

 -spec lambda_lift(fcode()) -> fcode().
-lambda_lift(FCode = #{ functions := Funs }) ->
-    init_fresh_names(),
+lambda_lift(FCode = #{ functions := Funs, state_layout := StateLayout }) ->
    init_lambda_funs(),
-    Funs1   = maps:map(fun lambda_lift_fun/2, Funs),
+    Funs1   = maps:map(fun(_, Body) -> lambda_lift_fun(StateLayout, Body) end, Funs),
    NewFuns = get_lambda_funs(),
-    clear_fresh_names(),
    FCode#{ functions := maps:merge(Funs1, NewFuns) }.

 -define(lambda_key, '%lambdalifted').
@@ -1009,8 +1111,8 @@ add_lambda_fun(Def) ->
    put(?lambda_key, Funs#{ Name => Def }),
    Name.

-lambda_lift_fun(_, Def = #{ body := Body }) ->
-    Def#{ body := lambda_lift_expr(Body) }.
+lambda_lift_fun(Layout, Def = #{ body := Body }) ->
+    Def#{ body := lambda_lift_expr(Layout, Body) }.

 lifted_fun([Z], Xs, Body) ->
    #{ attrs  => [private],
@@ -1031,10 +1133,10 @@ make_closure(FVs, Xs, Body) ->
    Tup = fun([Y]) -> Y; (Ys) -> {tuple, Ys} end,
    {closure, Fun, Tup([{var, Y} || Y <- FVs])}.

-lambda_lift_expr({lam, Xs, Body}) ->
+lambda_lift_expr(Layout, {lam, Xs, Body}) ->
    FVs   = free_vars({lam, Xs, Body}),
-    make_closure(FVs, Xs, lambda_lift_expr(Body));
-lambda_lift_expr(UExpr) when element(1, UExpr) == def_u; element(1, UExpr) == builtin_u ->
+    make_closure(FVs, Xs, lambda_lift_expr(Layout, Body));
+lambda_lift_expr(Layout, UExpr) when element(1, UExpr) == def_u; element(1, UExpr) == builtin_u ->
    [Tag, F, Ar | _] = tuple_to_list(UExpr),
    ExtraArgs = case UExpr of
                    {builtin_u, _, _, TypeArgs} -> TypeArgs;
@@ -1043,40 +1145,42 @@ lambda_lift_expr(UExpr) when element(1, UExpr) == def_u; element(1, UExpr) == bu
    Xs   = [ lists:concat(["arg", I]) || I <- lists:seq(1, Ar) ],
    Args = [{var, X} || X <- Xs] ++ ExtraArgs,
    Body = case Tag of
-               builtin_u -> builtin_to_fcode(F, Args);
+               builtin_u -> builtin_to_fcode(Layout, F, Args);
               def_u     -> {def, F, Args}
           end,
    make_closure([], Xs, Body);
-lambda_lift_expr({remote_u, ArgsT, RetT, Ct, F}) ->
+lambda_lift_expr(Layout, {remote_u, ArgsT, RetT, Ct, F}) ->
    FVs  = free_vars(Ct),
-    Ct1  = lambda_lift_expr(Ct),
+    Ct1  = lambda_lift_expr(Layout, Ct),
    GasAndValueArgs = 2,
    Xs   = [ lists:concat(["arg", I]) || I <- lists:seq(1, length(ArgsT) + GasAndValueArgs) ],
    Args = [{var, X} || X <- Xs],
    make_closure(FVs, Xs, {remote, ArgsT, RetT, Ct1, F, Args});
-lambda_lift_expr(Expr) ->
+lambda_lift_expr(Layout, Expr) ->
    case Expr of
        {lit, _}               -> Expr;
        nil                    -> Expr;
        {var, _}               -> Expr;
        {closure, _, _}        -> Expr;
-        {def, D, As}           -> {def, D, lambda_lift_exprs(As)};
-        {builtin, B, As}       -> {builtin, B, lambda_lift_exprs(As)};
-        {remote, ArgsT, RetT, Ct, F, As} -> {remote, ArgsT, RetT, lambda_lift_expr(Ct), F, lambda_lift_exprs(As)};
-        {con, Ar, C, As}       -> {con, Ar, C, lambda_lift_exprs(As)};
-        {tuple, As}            -> {tuple, lambda_lift_exprs(As)};
-        {proj, A, I}           -> {proj, lambda_lift_expr(A), I};
-        {set_proj, A, I, B}    -> {set_proj, lambda_lift_expr(A), I, lambda_lift_expr(B)};
-        {op, Op, As}           -> {op, Op, lambda_lift_exprs(As)};
-        {'let', X, A, B}       -> {'let', X, lambda_lift_expr(A), lambda_lift_expr(B)};
-        {funcall, A, Bs}       -> {funcall, lambda_lift_expr(A), lambda_lift_exprs(Bs)};
-        {switch, S}            -> {switch, lambda_lift_expr(S)};
-        {split, Type, X, Alts} -> {split, Type, X, lambda_lift_exprs(Alts)};
-        {nosplit, A}           -> {nosplit, lambda_lift_expr(A)};
-        {'case', P, S}         -> {'case', P, lambda_lift_expr(S)}
+        {def, D, As}           -> {def, D, lambda_lift_exprs(Layout, As)};
+        {builtin, B, As}       -> {builtin, B, lambda_lift_exprs(Layout, As)};
+        {remote, ArgsT, RetT, Ct, F, As} -> {remote, ArgsT, RetT, lambda_lift_expr(Layout, Ct), F, lambda_lift_exprs(Layout, As)};
+        {con, Ar, C, As}       -> {con, Ar, C, lambda_lift_exprs(Layout, As)};
+        {tuple, As}            -> {tuple, lambda_lift_exprs(Layout, As)};
+        {proj, A, I}           -> {proj, lambda_lift_expr(Layout, A), I};
+        {set_proj, A, I, B}    -> {set_proj, lambda_lift_expr(Layout, A), I, lambda_lift_expr(Layout, B)};
+        {op, Op, As}           -> {op, Op, lambda_lift_exprs(Layout, As)};
+        {'let', X, A, B}       -> {'let', X, lambda_lift_expr(Layout, A), lambda_lift_expr(Layout, B)};
+        {funcall, A, Bs}       -> {funcall, lambda_lift_expr(Layout, A), lambda_lift_exprs(Layout, Bs)};
+        {set_state, R, A}      -> {set_state, R, lambda_lift_expr(Layout, A)};
+        {get_state, _}         -> Expr;
+        {switch, S}            -> {switch, lambda_lift_expr(Layout, S)};
+        {split, Type, X, Alts} -> {split, Type, X, lambda_lift_exprs(Layout, Alts)};
+        {nosplit, A}           -> {nosplit, lambda_lift_expr(Layout, A)};
+        {'case', P, S}         -> {'case', P, lambda_lift_expr(Layout, S)}
    end.

-lambda_lift_exprs(As) -> [lambda_lift_expr(A) || A <- As].
+lambda_lift_exprs(Layout, As) -> [lambda_lift_expr(Layout, A) || A <- As].

 %% -- Optimisations ----------------------------------------------------------

@@ -1094,7 +1198,12 @@ optimize_fcode(Code = #{ functions := Funs }) ->
 -spec optimize_fun(fcode(), fun_name(), fun_def()) -> fun_def().
 optimize_fun(Fcode, Fun, Def = #{ body := Body }) ->
    %% io:format("Optimizing ~p =\n~s\n", [_Fun, prettypr:format(pp_fexpr(_Body))]),
-    Def#{ body := inliner(Fcode, Fun, Body) }.
+    Def#{ body := drop_unused_lets(
+                  simplifier(
+                  let_floating(
+                  bind_subexpressions(
+                  inline_local_functions(
+                  inliner(Fcode, Fun, Body)))))) }.

 %% --- Inlining ---

@@ -1110,6 +1219,276 @@ should_inline(_Fcode, _Fun1) -> false == list_to_atom("true").  %% Dialyzer

 inline(_Fcode, Fun, Args) -> {def, Fun, Args}. %% TODO

+%% --- Bind subexpressions ---
+
+-define(make_lets(Xs, Es, Body), make_lets(Es, fun(Xs) -> Body end)).
+
+bind_subexpressions(Expr) ->
+    bottom_up(fun bind_subexpressions/2, Expr).
+
+bind_subexpressions(_, {tuple, Es}) ->
+    ?make_lets(Xs, Es, {tuple, Xs});
+bind_subexpressions(_, {set_proj, A, I, B}) ->
+    ?make_lets([X, Y], [A, B], {set_proj, X, I, Y});
+bind_subexpressions(_, E) -> E.
+
+make_lets(Es, Body) -> make_lets(Es, [], Body).
+
+make_lets([], Xs, Body)       -> Body(lists:reverse(Xs));
+make_lets([{var, _} = E | Es], Xs, Body) ->
+    make_lets(Es, [E | Xs], Body);
+make_lets([{lit, _} = E | Es], Xs, Body) ->
+    make_lets(Es, [E | Xs], Body);
+make_lets([E | Es], Xs, Body) ->
+    ?make_let(X, E, make_lets(Es, [X | Xs], Body)).
+
+%% --- Inline local functions ---
+
+inline_local_functions(Expr) ->
+    bottom_up(fun inline_local_functions/2, Expr).
+
+inline_local_functions(Env, {funcall, {proj, {var, Y}, 0}, [{proj, {var, Y}, 1} | Args]} = Expr) ->
+    %% TODO: Don't always inline local funs?
+    case maps:get(Y, Env, free) of
+        {lam, Xs, Body} -> let_bind(lists:zip(Xs, Args), Body);
+        _               -> Expr
+    end;
+inline_local_functions(_, Expr) -> Expr.
+
+%% --- Let-floating ---
+
+let_floating(Expr) -> bottom_up(fun let_float/2, Expr).
+
+let_float(_, {'let', X, E, Body}) ->
+    pull_out_let({'let', X, {here, E}, Body});
+let_float(_, {proj, E, I}) ->
+    pull_out_let({proj, {here, E}, I});
+let_float(_, {set_proj, E, I, V}) ->
+    pull_out_let({set_proj, {here, E}, I, {here, V}});
+let_float(_, {op, Op, Es}) ->
+    {Lets, Es1} = pull_out_let([{here, E} || E <- Es]),
+    let_bind(Lets, {op, Op, Es1});
+let_float(_, E) -> E.
+
+pull_out_let(Expr) when is_tuple(Expr) ->
+    {Lets, Es} = pull_out_let(tuple_to_list(Expr)),
+    Inner = list_to_tuple(Es),
+    let_bind(Lets, Inner);
+pull_out_let(Es) when is_list(Es) ->
+    case lists:splitwith(fun({here, _}) -> false; (_) -> true end, Es) of
+        {Es0, [{here, E} | Es1]} ->
+            case let_view(E) of
+                {[], _}    ->
+                    {Lets, Es2} = pull_out_let(Es1),
+                    {Lets, Es0 ++ [E] ++ Es2};
+                {Lets, E1} ->
+                    {Lets1, Es2} = pull_out_let(Es1),
+                    {Lets ++ Lets1, Es0 ++ [E1] ++ Es2}
+            end;
+        {_, []} -> {[], Es}
+    end.
+
+%% Also renames the variables to fresh names
+let_view(E) -> let_view(E, [], []).
+
+let_view({'let', X, E, Rest}, Ren, Lets) ->
+    Z = fresh_name(),
+    let_view(Rest, [{X, Z} | Ren], [{Z, rename(Ren, E)} | Lets]);
+let_view(E, Ren, Lets) ->
+    {lists:reverse(Lets), rename(Ren, E)}.
+
+%% --- Simplification ---
+
+-spec simplifier(fexpr()) -> fexpr().
+simplifier(Expr) ->
+    bottom_up(fun simplify/2, Expr).
+
+-spec simplify(#{var_name() => fexpr()}, fexpr()) -> fexpr().
+
+%% (e₀, .., en).i ->
+%% let _ = e₀ in .. let x = ei in .. let _ = en in x
+simplify(_Env, {proj, {tuple, Es}, I}) ->
+    It  = lists:nth(I + 1, Es),
+    X   = fresh_name(),
+    Dup = safe_to_duplicate(It),
+    Val = if Dup -> It; true -> {var, X} end,
+    lists:foldr(
+      fun({J, E}, Rest) when I == J ->
+            case Dup of
+                true  -> Rest;
+                false -> {'let', X, E, Rest}
+            end;
+         ({_, E}, Rest) ->
+            case read_only(E) of
+                true  -> Rest;
+                false -> {'let', "_", E, Rest}
+            end
+        end, Val, indexed(Es));
+
+%% let x = e in .. x.i ..
+simplify(Env, {proj, {var, X}, I} = Expr) ->
+    case simpl_proj(Env, I, {var, X}) of
+        false -> Expr;
+        E     -> E
+    end;
+
+simplify(Env, {switch, Split}) ->
+    case simpl_switch(Env, [], Split) of
+        nomatch -> {builtin, abort, [{lit, {string, <<"Incomplete patterns">>}}]};
+        stuck   -> {switch, Split};
+        Expr    -> Expr
+    end;
+
+simplify(_, E) ->
+    E.
+
+simpl_proj(Env, I, Expr) ->
+    IfSafe = fun(E) -> case safe_to_duplicate(E) of
+                         true -> E;
+                         false -> false
+                       end end,
+    case Expr of
+        false                 -> false;
+        {var, X}              -> simpl_proj(Env, I, maps:get(X, Env, false));
+        {tuple, Es}           -> IfSafe(lists:nth(I + 1, Es));
+        {set_proj, _, I, Val} -> IfSafe(Val);
+        {set_proj, E, _, _}   -> simpl_proj(Env, I, E);
+        {proj, E, J}          -> simpl_proj(Env, I, simpl_proj(Env, J, E));
+        _                     -> false
+    end.
+
+get_catchalls(Alts) ->
+    [ C || C = {'case', {var, _}, _} <- Alts ].
+
+%% The scode compiler can't handle multiple catch-alls, so we need to nest them
+%% inside each other. Instead of
+%%    _ => switch(x) ..
+%%    _ => e
+%% we do
+%%    _ => switch(x)
+%%           ..
+%%           _ => e
+add_catchalls(Alts, []) -> Alts;
+add_catchalls(Alts, Catchalls) ->
+    case lists:splitwith(fun({'case', {var, _}, _}) -> false; (_) -> true end,
+                         Alts) of
+        {Alts1, [C]} -> Alts1 ++ [nest_catchalls([C | Catchalls])];
+        {_, []}      -> Alts  ++ [nest_catchalls(Catchalls)]
+        %% NOTE: relies on catchalls always being at the end
+    end.
+
+nest_catchalls([C = {'case', {var, _}, {nosplit, _}} | _]) -> C;
+nest_catchalls([{'case', P = {var, _}, {split, Type, X, Alts}} | Catchalls]) ->
+    {'case', P, {split, Type, X, add_catchalls(Alts, Catchalls)}}.
+
+simpl_switch(_Env, _, {nosplit, E}) -> E;
+simpl_switch(Env, Catchalls, {split, Type, X, Alts}) ->
+    Alts1 = add_catchalls(Alts, Catchalls),
+    Stuck = {switch, {split, Type, X, Alts1}},
+    case constructor_form(Env, {var, X}) of
+        false -> Stuck;
+        E     ->
+            case simpl_case(Env, E, Alts1) of
+                stuck -> Stuck;
+                Res   -> Res
+            end
+    end.
+
+simpl_case(_, _, []) -> nomatch;
+simpl_case(Env, E, [{'case', Pat, Body} | Alts]) ->
+    case match_pat(Pat, E) of
+        false -> simpl_case(Env, E, Alts);
+        Binds ->
+            Env1 = maps:merge(Env, maps:from_list(Binds)),
+            case simpl_switch(Env1, get_catchalls(Alts), Body) of
+                nomatch -> simpl_case(Env, E, Alts);
+                stuck   -> stuck;
+                Body1   -> let_bind(Binds, Body1)
+            end
+    end.
+
+-spec match_pat(fsplit_pat(), fexpr()) -> false | [{var_name(), fexpr()}].
+match_pat({tuple, Xs}, {tuple, Es})         -> lists:zip(Xs, Es);
+match_pat({con, _, C, Xs}, {con, _, C, Es}) -> lists:zip(Xs, Es);
+match_pat(L, {lit, L})                      -> [];
+match_pat(nil, nil)                         -> [];
+match_pat({'::', X, Y}, {op, '::', [A, B]}) -> [{X, A}, {Y, B}];
+match_pat({var, X}, E)                      -> [{X, E}];
+match_pat(_, _)                             -> false.
+
+constructor_form(Env, Expr) ->
+    case Expr of
+        {var, X} ->
+            case maps:get(X, Env, free) of
+                free -> false;
+                E    -> constructor_form(Env, E)    %% TODO: shadowing?
+            end;
+        {set_proj, E, I, V} ->
+            case constructor_form(Env, E) of
+                {tuple, Es} -> {tuple, setnth(I + 1, V, Es)};
+                _           -> false
+            end;
+        {proj, E, I} ->
+            case constructor_form(Env, E) of
+                {tuple, Es} -> constructor_form(Env, lists:nth(I + 1, Es));
+                _           -> false
+            end;
+        {con, _, _, _} -> Expr;
+        {tuple, _}     -> Expr;
+        {lit, _}       -> Expr;
+        nil            -> Expr;
+        {op, '::', _}  -> Expr;
+        _              -> false
+    end.
+
+%% --- Drop unused lets ---
+
+drop_unused_lets(Expr) -> bottom_up(fun drop_unused_lets/2, Expr).
+
+drop_unused_lets(_, {'let', X, E, Body} = Expr) ->
+    case {read_only(E), not lists:member(X, free_vars(Body))} of
+        {true, true}  -> Body;
+        {false, true} -> {'let', "_", E, Body};
+        _             -> Expr
+    end;
+drop_unused_lets(_, Expr) -> Expr.
+
+%% -- Static analysis --------------------------------------------------------
+
+safe_to_duplicate({lit, _})    -> true;
+safe_to_duplicate({var, _})    -> true;
+safe_to_duplicate(nil)         -> true;
+safe_to_duplicate({tuple, []}) -> true;
+safe_to_duplicate(_)           -> false.
+
+-spec read_only(fexpr() | fsplit() | fcase() | [fexpr()] | [fcase()]) -> boolean().
+read_only({lit, _})                -> true;
+read_only({var, _})                -> true;
+read_only(nil)                     -> true;
+read_only({con, _, _, Es})         -> read_only(Es);
+read_only({tuple, Es})             -> read_only(Es);
+read_only({proj, E, _})            -> read_only(E);
+read_only({set_proj, A, _, B})     -> read_only([A, B]);
+read_only({op, _, Es})             -> read_only(Es);
+read_only({get_state, _})          -> true;
+read_only({set_state, _, _})       -> false;
+read_only({def_u, _, _})           -> true;
+read_only({remote_u, _, _, _, _})  -> true;
+read_only({builtin_u, _, _})       -> true;
+read_only({builtin_u, _, _, _})    -> true;
+read_only({lam, _, _})             -> true;
+read_only({def, _, _})             -> false; %% TODO: purity analysis
+read_only({remote, _, _, _, _, _}) -> false;
+read_only({builtin, _, _})         -> false; %% TODO: some builtins are
+read_only({switch, Split})         -> read_only(Split);
+read_only({split, _, _, Cases})    -> read_only(Cases);
+read_only({nosplit, E})            -> read_only(E);
+read_only({'case', _, Split})      -> read_only(Split);
+read_only({'let', _, A, B})        -> read_only([A, B]);
+read_only({funcall, _, _})         -> false;
+read_only({closure, _, _})         -> internal_error(no_closures_here);
+read_only(Es) when is_list(Es)     -> lists:all(fun read_only/1, Es).
+
 %% --- Deadcode elimination ---

 -spec eliminate_dead_code(fcode()) -> fcode().
@@ -1231,10 +1610,10 @@ resolve_var(#{ vars := Vars } = Env, [X]) ->
    end;
 resolve_var(Env, Q) -> resolve_fun(Env, Q).

-resolve_fun(#{ fun_env := Funs, builtins := Builtin }, Q) ->
+resolve_fun(#{ fun_env := Funs, builtins := Builtin } = Env, Q) ->
    case {maps:get(Q, Funs, not_found), maps:get(Q, Builtin, not_found)} of
        {not_found, not_found} -> internal_error({unbound_variable, Q});
-        {_, {B, none}}         -> {builtin, B, []};
+        {_, {B, none}}         -> builtin_to_fcode(state_layout(Env), B, []);
        {_, {B, Ar}}           -> {builtin_u, B, Ar};
        {{Fun, Ar}, _}         -> {def_u, Fun, Ar}
    end.
@@ -1299,6 +1678,8 @@ free_vars(Expr) ->
        {op, _, As}          -> free_vars(As);
        {'let', X, A, B}     -> free_vars([A, {lam, [X], B}]);
        {funcall, A, Bs}     -> free_vars([A | Bs]);
+        {set_state, _, A}    -> free_vars(A);
+        {get_state, _}       -> [];
        {lam, Xs, B}         -> free_vars(B) -- lists:sort(Xs);
        {closure, _, A}      -> free_vars(A);
        {switch, A}          -> free_vars(A);
@@ -1328,6 +1709,8 @@ used_defs(Expr) ->
        {op, _, As}          -> used_defs(As);
        {'let', _, A, B}     -> used_defs([A, B]);
        {funcall, A, Bs}     -> used_defs([A | Bs]);
+        {set_state, _, A}    -> used_defs(A);
+        {get_state, _}       -> [];
        {lam, _, B}          -> used_defs(B);
        {closure, F, A}      -> lists:umerge([F], used_defs(A));
        {switch, A}          -> used_defs(A);
@@ -1336,6 +1719,50 @@ used_defs(Expr) ->
        {'case', _, A}       -> used_defs(A)
    end.

+bottom_up(F, Expr) -> bottom_up(F, #{}, Expr).
+
+bottom_up(F, Env, Expr) ->
+    F(Env, case Expr of
+        {lit, _}                         -> Expr;
+        nil                              -> Expr;
+        {var, _}                         -> Expr;
+        {def, D, Es}                     -> {def, D, [bottom_up(F, Env, E) || E <- Es]};
+        {def_u, _, _}                    -> Expr;
+        {builtin, B, Es}                 -> {builtin, B, [bottom_up(F, Env, E) || E <- Es]};
+        {builtin_u, _, _}                -> Expr;
+        {builtin_u, _, _, _}             -> Expr;
+        {remote, ArgsT, RetT, Ct, Fun, Es} -> {remote,   ArgsT, RetT, bottom_up(F, Env, Ct), Fun, [bottom_up(F, Env, E) || E <- Es]};
+        {remote_u, ArgsT, RetT, Ct, Fun}   -> {remote_u, ArgsT, RetT, bottom_up(F, Env, Ct), Fun};
+        {con, Ar, I, Es}                 -> {con, Ar, I, [bottom_up(F, Env, E) || E <- Es]};
+        {tuple, Es}                      -> {tuple, [bottom_up(F, Env, E) || E <- Es]};
+        {proj, E, I}                     -> {proj, bottom_up(F, Env, E), I};
+        {set_proj, R, I, E}              -> {set_proj, bottom_up(F, Env, R), I, bottom_up(F, Env, E)};
+        {op, Op, Es}                     -> {op, Op, [bottom_up(F, Env, E) || E <- Es]};
+        {funcall, Fun, Es}               -> {funcall, bottom_up(F, Env, Fun), [bottom_up(F, Env, E) || E <- Es]};
+        {set_state, R, E}                -> {set_state, R, bottom_up(F, Env, E)};
+        {get_state, _}                   -> Expr;
+        {closure, F, CEnv}               -> {closure, F, bottom_up(F, Env, CEnv)};
+        {switch, Split}                  -> {switch, bottom_up(F, Env, Split)};
+        {lam, Xs, B}                     -> {lam, Xs, bottom_up(F, Env, B)};
+        {'let', X, E, Body}              ->
+            E1 = bottom_up(F, Env, E),
+            %% Always freshen user variables to avoid shadowing issues.
+            ShouldFreshen = fun(Y = "%" ++ _) -> maps:is_key(Y, Env);
+                               (_)            -> true end,
+            case ShouldFreshen(X) of
+                true ->
+                    Z = fresh_name(),
+                    Env1 = Env#{ Z => E1 },
+                    {'let', Z, E1, bottom_up(F, Env1, rename([{X, Z}], Body))};
+                false ->
+                    Env1 = Env#{ X => E1 },
+                    {'let', X, E1, bottom_up(F, Env1, Body)}
+            end;
+        {split, Type, X, Cases}          -> {split, Type, X, [bottom_up(F, Env, Case) || Case <- Cases]};
+        {nosplit, E}                     -> {nosplit, bottom_up(F, Env, E)};
+        {'case', Pat, Split}             -> {'case', Pat, bottom_up(F, Env, Split)}
+    end).
+
 get_named_args(NamedArgsT, Args) ->
    IsNamed = fun({named_arg, _, _, _}) -> true;
                 (_) -> false end,
@@ -1370,6 +1797,8 @@ rename(Ren, Expr) ->
        {set_proj, R, I, E}   -> {set_proj, rename(Ren, R), I, rename(Ren, E)};
        {op, Op, Es}          -> {op, Op, [rename(Ren, E) || E <- Es]};
        {funcall, Fun, Es}    -> {funcall, rename(Ren, Fun), [rename(Ren, E) || E <- Es]};
+        {set_state, R, E}     -> {set_state, R, rename(Ren, E)};
+        {get_state, _}        -> Expr;
        {closure, F, Env}     -> {closure, F, rename(Ren, Env)};
        {switch, Split}       -> {switch, rename_split(Ren, Split)};
        {lam, Xs, B} ->
@@ -1476,6 +1905,10 @@ get_attributes(Ann) ->
 indexed(Xs) ->
    lists:zip(lists:seq(1, length(Xs)), Xs).

+setnth(I, X, Xs) ->
+    {Ys, [_ | Zs]} = lists:split(I - 1, Xs),
+    Ys ++ [X] ++ Zs.
+
 -dialyzer({nowarn_function, [fcode_error/1, internal_error/1]}).

 fcode_error(Error) ->
@@ -1578,9 +2011,18 @@ pp_fexpr({op, Op, [A] = Args}) ->
    end;
 pp_fexpr({op, Op, As}) ->
    pp_beside(pp_text(Op), pp_fexpr({tuple, As}));
-pp_fexpr({'let', X, A, B}) ->
-    pp_par([pp_beside([pp_text("let "), pp_text(X), pp_text(" = "), pp_fexpr(A), pp_text(" in")]),
-            pp_fexpr(B)]);
+pp_fexpr({'let', _, _, _} = Expr) ->
+    Lets = fun Lets({'let', Y, C, D}) ->
+                        {Ls, E} = Lets(D),
+                        {[{Y, C} | Ls], E};
+               Lets(E) -> {[], E} end,
+    {Ls, Body} = Lets(Expr),
+    pp_parens(
+      pp_par(
+        [ pp_beside([ pp_text("let "),
+                      pp_above([ pp_par([pp_text(X), pp_text("="), prettypr:nest(2, pp_fexpr(A))]) || {X, A} <- Ls ]),
+                      pp_text(" in ") ]),
+          pp_fexpr(Body) ]));
 pp_fexpr({builtin_u, B, N}) ->
    pp_beside([pp_text(B), pp_text("/"), pp_text(N)]);
 pp_fexpr({builtin_u, B, N, TypeArgs}) ->
@@ -1593,6 +2035,10 @@ pp_fexpr({remote, ArgsT, RetT, Ct, Fun, As}) ->
    pp_call(pp_parens(pp_beside([pp_fexpr(Ct), pp_text("."), pp_fun_name(Fun), pp_text(" : "), pp_ftype({function, ArgsT, RetT})])), As);
 pp_fexpr({funcall, Fun, As}) ->
    pp_call(pp_fexpr(Fun), As);
+pp_fexpr({set_state, R, A}) ->
+    pp_call(pp_text("set_state"), [{lit, {int, R}}, A]);
+pp_fexpr({get_state, R}) ->
+    pp_call(pp_text("get_state"), [{lit, {int, R}}]);
 pp_fexpr({switch, Split}) -> pp_split(Split).

 pp_call(Fun, Args) ->
@@ -1608,7 +2054,7 @@ pp_ftype({tvar, X}) -> pp_text(X);
 pp_ftype({bytes, N}) -> pp_call(pp_text("bytes"), [{lit, {int, N}}]);
 pp_ftype({oracle, Q, R}) -> pp_call_t("oracle", [Q, R]);
 pp_ftype({tuple, Ts}) ->
-    pp_parens(pp_par(pp_punctuate(pp_text(","), [pp_ftype(T) || T <- Ts])));
+    pp_parens(pp_par(pp_punctuate(pp_text(" *"), [pp_ftype(T) || T <- Ts])));
 pp_ftype({list, T}) ->
    pp_call_t("list", [T]);
 pp_ftype({function, Args, Res}) ->
@@ -131,7 +131,7 @@ contract_to_icode([Decl | Code], Icode) ->
 ast_id({id, _, Id}) -> Id;
 ast_id({qid, _, Id}) -> Id.

-ast_args([{arg, _, Name, Type}|Rest], Acc, Icode) ->
+ast_args([{typed, _, Name, Type}|Rest], Acc, Icode) ->
    ast_args(Rest, [{ast_id(Name), ast_typerep1(Type, Icode)}| Acc], Icode);
 ast_args([], Acc, _Icode) -> lists:reverse(Acc).

@@ -318,19 +318,23 @@ ast_body({app, As, Fun, Args}, Icode) ->
    end;
 ast_body({list_comp, _, Yield, []}, Icode) ->
    #list{elems = [ast_body(Yield, Icode)]};
-ast_body({list_comp, As, Yield, [{comprehension_bind, {typed, Arg, ArgType}, BindExpr}|Rest]}, Icode) ->
+ast_body({list_comp, As, Yield, [{comprehension_bind, {typed, _, Pat, ArgType}, BindExpr}|Rest]}, Icode) ->
+    Arg  = "%lc",
+    Body = {switch, As, {typed, As, {id, As, Arg}, ArgType},
+                [{'case', As, Pat, {list_comp, As, Yield, Rest}},
+                 {'case', As, {id, As, "_"}, {list, As, []}}]},
    #funcall
        { function = #var_ref{ name = ["ListInternal", "flat_map"] }
        , args =
-              [ #lambda{ args=[#arg{name = ast_id(Arg), type = ast_type(ArgType, Icode)}]
-                       , body = ast_body({list_comp, As, Yield, Rest}, Icode)
+              [ #lambda{ args=[#arg{name = Arg, type = ast_type(ArgType, Icode)}]
+                       , body = ast_body(Body, Icode)
                       }
              , ast_body(BindExpr, Icode)
              ]
        };
 ast_body({list_comp, As, Yield, [{comprehension_if, AsIF, Cond}|Rest]}, Icode) ->
    ast_body({'if', AsIF, Cond, {list_comp, As, Yield, Rest}, {list, As, []}}, Icode);
-ast_body({list_comp, As, Yield, [LV = {letval, _, _, _, _}|Rest]}, Icode) ->
+ast_body({list_comp, As, Yield, [LV = {letval, _, _, _}|Rest]}, Icode) ->
    ast_body({block, As, [LV, {list_comp, As, Yield, Rest}]}, Icode);
 ast_body({list_comp, As, Yield, [LF = {letfun, _, _, _, _, _}|Rest]}, Icode) ->
    ast_body({block, As, [LF, {list_comp, As, Yield, Rest}]}, Icode);
@@ -344,14 +348,16 @@ ast_body({switch,_,A,Cases}, Icode) ->
    #switch{expr=ast_body(A, Icode),
            cases=[{ast_body(Pat, Icode),ast_body(Body, Icode)}
              || {'case',_,Pat,Body} <- Cases]};
-ast_body({block, As, [{letval, _, Pat, _, E} | Rest]}, Icode) ->
+ast_body({block, As, [{letval, _, Pat, E} | Rest]}, Icode) ->
    E1    = ast_body(E, Icode),
    Pat1  = ast_body(Pat, Icode),
    Rest1 = ast_body({block, As, Rest}, Icode),
    #switch{expr  = E1,
            cases = [{Pat1, Rest1}]};
 ast_body({block, As, [{letfun, Ann, F, Args, _Type, Expr} | Rest]}, Icode) ->
-    ast_body({block, As, [{letval, Ann, F, unused, {lam, Ann, Args, Expr}} | Rest]}, Icode);
+    ToArg   = fun({typed, Ann1, Id, T}) -> {arg, Ann1, Id, T} end,    %% Pattern matching has been desugared
+    LamArgs = lists:map(ToArg, Args),
+    ast_body({block, As, [{letval, Ann, F, {lam, Ann, LamArgs, Expr}} | Rest]}, Icode);
 ast_body({block,_,[]}, _Icode) ->
    #tuple{cpts=[]};
 ast_body({block,_,[E]}, Icode) ->
@@ -494,6 +500,7 @@ is_builtin_fun({qid, _, ["Address", "to_str"]}, _Icode)                      ->
 is_builtin_fun({qid, _, ["Address", "is_oracle"]}, _Icode)                   -> true;
 is_builtin_fun({qid, _, ["Address", "is_contract"]}, _Icode)                 -> true;
 is_builtin_fun({qid, _, ["Address", "is_payable"]}, _Icode)                  -> true;
+is_builtin_fun({qid, _, ["Address", "to_contract"]}, _Icode)                 -> true;
 is_builtin_fun({qid, _, ["Bytes", "to_int"]}, _Icode)                        -> true;
 is_builtin_fun({qid, _, ["Bytes", "to_str"]}, _Icode)                        -> true;
 is_builtin_fun({qid, _, ["Bytes", "concat"]}, _Icode)                        -> true;
@@ -713,6 +720,8 @@ builtin_code(_, {qid, _, ["Address", "is_contract"]}, [Addr], _, _, Icode) ->
 builtin_code(_, {qid, _, ["Address", "is_payable"]}, [Addr], _, _, Icode) ->
    prim_call(?PRIM_CALL_ADDR_IS_PAYABLE, #integer{value = 0},
              [ast_body(Addr, Icode)], [word], word);
+builtin_code(_, {qid, _, ["Address", "to_contract"]}, [Addr], _, _, Icode) ->
+    ast_body(Addr, Icode);

 builtin_code(_, {qid, _, ["Bytes", "to_int"]}, [Bytes], _, _, Icode) ->
    {typed, _, _, {bytes_t, _, N}} = Bytes,
@@ -797,10 +806,10 @@ check_entrypoint_type(Ann, Name, Args, Ret) ->
                    true  -> ok
                end end,
    [ CheckFirstOrder(T, {invalid_entrypoint, higher_order, Ann1, Name, {argument, X, T}})
-      || {arg, Ann1, X, T} <- Args ],
+      || {typed, Ann1, X, T} <- Args ],
    CheckFirstOrder(Ret, {invalid_entrypoint, higher_order, Ann, Name, {result, Ret}}),
    [ CheckMonomorphic(T, {invalid_entrypoint, polymorphic, Ann1, Name, {argument, X, T}})
-      || {arg, Ann1, X, T} <- Args ],
+      || {typed, Ann1, X, T} <- Args ],
    CheckMonomorphic(Ret, {invalid_entrypoint, polymorphic, Ann, Name, {result, Ret}}).

 check_oracle_type(Ann, Type = ?oracle_t(QType, RType)) ->
@@ -15,6 +15,7 @@
        , create_calldata/3  %% deprecated
        , create_calldata/4
        , version/0
+        , numeric_version/0
        , sophia_type_to_typerep/1
        , to_sophia_value/4  %% deprecated, need a backend
        , to_sophia_value/5
@@ -22,6 +23,7 @@
        , decode_calldata/4
        , parse/2
        , add_include_path/2
+        , validate_byte_code/3
        ]).

 -include_lib("aebytecode/include/aeb_opcodes.hrl").
@@ -65,6 +67,17 @@ version() ->
            {ok, list_to_binary(VsnString)}
    end.

+-spec numeric_version() -> {ok, [non_neg_integer()]} | {error, term()}.
+numeric_version() ->
+    case version() of
+        {ok, Bin} ->
+            [NoSuf | _] = binary:split(Bin, <<"-">>),
+            Numbers     = binary:split(NoSuf, <<".">>, [global]),
+            {ok, [binary_to_integer(Num) || Num <- Numbers]};
+        {error, _} = Err ->
+            Err
+    end.
+
 -spec file(string()) -> {ok, map()} | {error, [aeso_errors:error()]}.
 file(Filename) ->
    file(Filename, []).
@@ -376,8 +389,8 @@ decode_calldata(ContractString, FunName, Calldata, Options0) ->
        #{ typed_ast := TypedAst, type_env  := TypeEnv} = Code,

        {ok, Args, _} = get_decode_type(FunName, TypedAst),
-        DropArg       = fun({arg, _, _, T}) -> T; (T) -> T end,
-        ArgTypes      = lists:map(DropArg, Args),
+        GetType       = fun({typed, _, _, T}) -> T; (T) -> T end,
+        ArgTypes      = lists:map(GetType, Args),
        Type0         = {tuple_t, [], ArgTypes},
        %% user defined data types such as variants needed to match against
        Type          = aeso_ast_infer_types:unfold_types_in_type(TypeEnv, Type0, [unfold_record_types, unfold_variant_types]),
@@ -495,6 +508,14 @@ icode_to_term(T = {map, KT, VT}, M) ->
            #{};
        _ -> throw({todo, M})
    end;
+icode_to_term(word, {unop, 'bnot', A}) ->
+    bnot icode_to_term(word, A);
+icode_to_term(word, {binop, 'bor', A, B}) ->
+    icode_to_term(word, A) bor icode_to_term(word, B);
+icode_to_term(word, {binop, 'bsl', A, B}) ->
+    icode_to_term(word, B) bsl icode_to_term(word, A);
+icode_to_term(word, {binop, 'band', A, B}) ->
+    icode_to_term(word, A) band icode_to_term(word, B);
 icode_to_term(typerep, _) ->
    throw({todo, typerep});
 icode_to_term(T, V) ->
@@ -546,6 +567,87 @@ pp(Code, Options, Option, PPFun) ->
            ok
    end.

+%% -- Byte code validation ---------------------------------------------------
+
+-define(protect(Tag, Code), fun() -> try Code catch _:Err1 -> throw({Tag, Err1}) end end()).
+
+-spec validate_byte_code(map(), string(), options()) -> ok | {error, [aeso_errors:error()]}.
+validate_byte_code(#{ byte_code := ByteCode, payable := Payable }, Source, Options) ->
+    Fail = fun(Err) -> {error, [aeso_errors:new(data_error, Err)]} end,
+    case proplists:get_value(backend, Options, aevm) of
+        B when B /= fate -> Fail(io_lib:format("Unsupported backend: ~s\n", [B]));
+        fate ->
+            try
+                FCode1 = ?protect(deserialize, aeb_fate_code:strip_init_function(aeb_fate_code:deserialize(ByteCode))),
+                {FCode2, SrcPayable} =
+                    ?protect(compile,
+                             begin
+                               {ok, #{ byte_code := SrcByteCode, payable := SrcPayable }} =
+                                    from_string1(fate, Source, Options),
+                               FCode = aeb_fate_code:deserialize(SrcByteCode),
+                               {aeb_fate_code:strip_init_function(FCode), SrcPayable}
+                             end),
+                case compare_fate_code(FCode1, FCode2) of
+                    ok when SrcPayable /= Payable ->
+                        Not = fun(true) -> ""; (false) -> " not" end,
+                        Fail(io_lib:format("Byte code contract is~s payable, but source code contract is~s.\n",
+                                           [Not(Payable), Not(SrcPayable)]));
+                    ok           -> ok;
+                    {error, Why} -> Fail(io_lib:format("Byte code does not match source code.\n~s", [Why]))
+                end
+            catch
+                throw:{deserialize, _}         -> Fail("Invalid byte code");
+                throw:{compile, {error, Errs}} -> {error, Errs}
+            end
+    end.
+
+compare_fate_code(FCode1, FCode2) ->
+    Funs1 = aeb_fate_code:functions(FCode1),
+    Funs2 = aeb_fate_code:functions(FCode2),
+    Syms1 = aeb_fate_code:symbols(FCode1),
+    Syms2 = aeb_fate_code:symbols(FCode2),
+    FunHashes1 = maps:keys(Funs1),
+    FunHashes2 = maps:keys(Funs2),
+    case FunHashes1 == FunHashes2 of
+        false ->
+            InByteCode   = [ binary_to_list(maps:get(H, Syms1)) || H <- FunHashes1 -- FunHashes2 ],
+            InSourceCode = [ binary_to_list(maps:get(H, Syms2)) || H <- FunHashes2 -- FunHashes1 ],
+            Msg = [ io_lib:format("- Functions in the byte code but not in the source code:\n"
+                                  "    ~s\n", [string:join(InByteCode, ", ")]) || InByteCode /= [] ] ++
+                  [ io_lib:format("- Functions in the source code but not in the byte code:\n"
+                                  "    ~s\n", [string:join(InSourceCode, ", ")]) || InSourceCode /= [] ],
+            {error, Msg};
+        true ->
+            case lists:append([ compare_fate_fun(maps:get(H, Syms1), Fun1, Fun2)
+                                || {{H, Fun1}, {_, Fun2}} <- lists:zip(maps:to_list(Funs1),
+                                                                       maps:to_list(Funs2)) ]) of
+                [] -> ok;
+                Errs -> {error, Errs}
+            end
+    end.
+
+compare_fate_fun(_Name, Fun, Fun) -> [];
+compare_fate_fun(Name, {Attr, Type, _}, {Attr, Type, _}) ->
+    [io_lib:format("- The implementation of the function ~s is different.\n", [Name])];
+compare_fate_fun(Name, {Attr1, Type, _}, {Attr2, Type, _}) ->
+    [io_lib:format("- The attributes of the function ~s differ:\n"
+                   "    Byte code:   ~s\n"
+                   "    Source code: ~s\n",
+                   [Name, string:join([ atom_to_list(A) || A <- Attr1 ], ", "),
+                          string:join([ atom_to_list(A) || A <- Attr2 ], ", ")])];
+compare_fate_fun(Name, {_, Type1, _}, {_, Type2, _}) ->
+    [io_lib:format("- The type of the function ~s differs:\n"
+                   "    Byte code:   ~s\n"
+                   "    Source code: ~s\n",
+                   [Name, pp_fate_sig(Type1), pp_fate_sig(Type2)])].
+
+pp_fate_sig({[Arg], Res}) ->
+    io_lib:format("~s => ~s", [pp_fate_type(Arg), pp_fate_type(Res)]);
+pp_fate_sig({Args, Res}) ->
+    io_lib:format("(~s) => ~s", [string:join([pp_fate_type(Arg) || Arg <- Args], ", "), pp_fate_type(Res)]).
+
+pp_fate_type(T) -> io_lib:format("~w", [T]).
+
 %% -------------------------------------------------------------------

 sophia_type_to_typerep(String) ->
@@ -50,7 +50,8 @@ parse_and_scan(P, S, Opts) ->
    set_current_file(proplists:get_value(src_file, Opts, no_file)),
    case aeso_scan:scan(S) of
        {ok, Tokens} -> aeso_parse_lib:parse(P, Tokens);
-        Error        -> Error
+        {error, {{Input, Pos}, _}} ->
+            {error, {Pos, scan_error, Input}}
    end.

 -dialyzer({nowarn_function, parse_error/1}).
@@ -60,8 +61,8 @@ parse_error(Err) ->
 mk_p_err(Pos, Msg) ->
    aeso_errors:new(parse_error, mk_pos(Pos), lists:flatten(Msg)).

-mk_error({Pos, ScanE}) when ScanE == scan_error; ScanE == scan_error_no_state ->
-    mk_p_err(Pos, "Scan error\n");
+mk_error({Pos, scan_error, Input}) ->
+    mk_p_err(Pos, io_lib:format("Lexical error on input: ~s\n", [Input]));
 mk_error({Pos, parse_error, Err}) ->
    Msg = io_lib:format("~s\n", [Err]),
    mk_p_err(Pos, Msg);
@@ -87,6 +88,7 @@ decl() ->
    , ?RULE(token(payable),     keyword(contract), con(), tok('='), maybe_block(decl()), add_modifiers([_1], {contract, _2, _3, _5}))
    , ?RULE(keyword(namespace), con(), tok('='), maybe_block(decl()), {namespace, _1, _2, _4})
    , ?RULE(keyword(include),   str(), {include, get_ann(_1), _2})
+    , pragma()

      %% Type declarations  TODO: format annotation for "type bla" vs "type bla()"
    , ?RULE(keyword(type),     id(),                                          {type_decl, _1, _2, []})
@@ -99,11 +101,29 @@ decl() ->
    , ?RULE(keyword(datatype), id(), type_vars(), tok('='), typedef(variant), {type_def, _1, _2, _3, _5})

      %% Function declarations
-    , ?RULE(modifiers(), fun_or_entry(), id(), tok(':'), type(), add_modifiers(_1, _2, {fun_decl, get_ann(_2), _3, _5}))
-    , ?RULE(modifiers(), fun_or_entry(), fundef(),               add_modifiers(_1, _2, set_pos(get_pos(get_ann(_2)), _3)))
-    , ?RULE(keyword('let'),    valdef(),                         set_pos(get_pos(_1), _2))
+    , ?RULE(modifiers(), fun_or_entry(), maybe_block(fundef_or_decl()), fun_block(_1, _2, _3))
+    , ?RULE(keyword('let'), valdef(),set_pos(get_pos(_1), _2))
    ])).

+fun_block(Mods, Kind, [Decl]) ->
+    add_modifiers(Mods, Kind, set_pos(get_pos(Kind), Decl));
+fun_block(Mods, Kind, Decls) ->
+    {block, get_ann(Kind), [ add_modifiers(Mods, Kind, Decl) || Decl <- Decls ]}.
+
+fundef_or_decl() ->
+    choice([?RULE(id(), tok(':'), type(), {fun_decl, get_ann(_1), _1, _3}),
+            fundef()]).
+
+pragma() ->
+    Op = choice([token(T) || T <- ['<', '=<', '==', '>=', '>']]),
+    ?RULE(tok('@'), id("compiler"), Op, version(), {pragma, get_ann(_1), {compiler, element(1, _3), _4}}).
+
+version() ->
+    ?RULE(token(int), many({tok('.'), token(int)}), mk_version(_1, _2)).
+
+mk_version({int, _, Maj}, Rest) ->
+    [Maj | [N || {_, {int, _, N}} <- Rest]].
+
 fun_or_entry() ->
    choice([?RULE(keyword(function),   {function,   _1}),
            ?RULE(keyword(entrypoint), {entrypoint, _1})]).
@@ -152,20 +172,19 @@ letdecl() ->
 letdef() -> choice(valdef(), fundef()).

 valdef() ->
-    choice(
-        ?RULE(id(),                   tok('='), body(), {letval, [], _1, type_wildcard(), _3}),
-        ?RULE(id(), tok(':'), type(), tok('='), body(), {letval, [], _1, _3, _5})).
+    ?RULE(pattern(), tok('='), body(), {letval, [], _1, _3}).

 fundef() ->
    choice(
-    [ ?RULE(id(), args(),                   tok('='), body(), {letfun, [], _1, _2, type_wildcard(), _4})
-    , ?RULE(id(), args(), tok(':'), type(), tok('='), body(), {letfun, [], _1, _2, _4, _6})
+    [ ?RULE(id(), args(),                   tok('='), body(), {letfun, get_ann(_1), _1, _2, type_wildcard(get_ann(_1)), _4})
+    , ?RULE(id(), args(), tok(':'), type(), tok('='), body(), {letfun, get_ann(_1), _1, _2, _4, _6})
    ]).

-args() -> paren_list(arg()).
+args() -> paren_list(pattern()).
+lam_args() -> paren_list(arg()).

 arg() -> choice(
-    ?RULE(id(),                   {arg, get_ann(_1), _1, type_wildcard()}),
+    ?RULE(id(),                   {arg, get_ann(_1), _1, type_wildcard(get_ann(_1))}),
    ?RULE(id(), tok(':'), type(), {arg, get_ann(_1), _1, _3})).

 %% -- Types ------------------------------------------------------------------
@@ -226,7 +245,7 @@ branch() ->
    ?RULE(pattern(), keyword('=>'), body(), {'case', _2, _1, _3}).

 pattern() ->
-    ?LET_P(E, expr500(), parse_pattern(E)).
+    ?LET_P(E, expr(), parse_pattern(E)).

 %% -- Expressions ------------------------------------------------------------

@@ -236,7 +255,7 @@ expr100() ->
    Expr100 = ?LAZY_P(expr100()),
    Expr200 = ?LAZY_P(expr200()),
    choice(
-    [ ?RULE(args(), keyword('=>'), body(), {lam, _2, _1, _3})   %% TODO: better location
+    [ ?RULE(lam_args(), keyword('=>'), body(), {lam, _2, _1, _3})   %% TODO: better location
    , {'if', keyword('if'), parens(Expr100), Expr200, right(tok(else), Expr100)}
    , ?RULE(Expr200, optional(right(tok(':'), type())),
            case _2 of
@@ -285,7 +304,7 @@ comprehension_if() ->
    ?RULE(keyword('if'), parens(expr()), {comprehension_if, _1, _2}).

 comprehension_bind() ->
-    ?RULE(id(), tok('<-'), expr(), {comprehension_bind, _1, _3}).
+    ?RULE(pattern(), tok('<-'), expr(), {comprehension_bind, _1, _3}).

 arg_expr() ->
    ?LAZY_P(
@@ -312,7 +331,7 @@ map_key(Key, {ok, {_, Val}}) -> {map_key, Key, Val}.

 elim(E, [])                              -> E;
 elim(E, [{proj, Ann, P} | Es])           -> elim({proj, Ann, E, P}, Es);
-elim(E, [{app, Ann, Args} | Es])         -> elim({app, Ann, E, Args}, Es);
+elim(E, [{app, _Ann, Args} | Es])        -> elim({app, aeso_syntax:get_ann(E), E, Args}, Es);
 elim(E, [{rec_upd, Ann, Flds} | Es])     -> elim(record_update(Ann, E, Flds), Es);
 elim(E, [{map_get, Ann, Key} | Es])      -> elim({map_get, Ann, E, Key}, Es);
 elim(E, [{map_get, Ann, Key, Val} | Es]) -> elim({map_get, Ann, E, Key, Val}, Es).
@@ -337,7 +356,9 @@ record(Fs) ->
                        bad_expr_err("Cannot use '@' in map construction", infix({lvalue, FAnn, LV}, {'@', Ann}, Id));
                    ({field, FAnn, LV, _}) ->
                        bad_expr_err("Cannot use nested fields or keys in map construction", {lvalue, FAnn, LV}) end,
-            {map, Ann, lists:map(KV, Fs)}
+            {map, Ann, lists:map(KV, Fs)};
+        record_or_map_error ->
+            {record_or_map_error, get_ann(hd(Fs)), Fs}
    end.

 record_or_map(Fields) ->
@@ -349,9 +370,7 @@ record_or_map(Fields) ->
    case lists:usort(lists:map(Kind, Fields)) of
        [proj]    -> record;
        [map_get] -> map;
-        _         ->
-            [{field, Ann, _, _} | _] = Fields,
-            bad_expr_err("Mixed record fields and map keys in", {record, Ann, Fields})
+        _         -> record_or_map_error %% Defer error until type checking
    end.

 field_assignment() ->
@@ -406,7 +425,7 @@ token(Tag) ->
 id(Id) ->
    ?LET_P({id, A, X} = Y, id(),
           if X == Id -> Y;
-              true    -> fail({A, "expected 'bytes'"})
+              true    -> fail({A, "expected '" ++ Id ++ "'"})
           end).

 id_or_addr() ->
@@ -482,8 +501,8 @@ infix(L, Op, R) -> set_ann(format, infix,  {app, get_ann(L), Op, [L, R]}).
 prefixes(Ops, E) -> lists:foldr(fun prefix/2, E, Ops).
 prefix(Op, E)    -> set_ann(format, prefix, {app, get_ann(Op), Op, [E]}).

-type_wildcard() ->
-    {id, [{origin, system}], "_"}.
+type_wildcard(Ann) ->
+    {id, [{origin, system} | Ann], "_"}.

 block_e(Stmts) ->
    group_ifs(Stmts, []).
@@ -533,7 +552,9 @@ list_comp_e(Ann, Expr, Binds) -> {list_comp, Ann, Expr, Binds}.
 -spec parse_pattern(aeso_syntax:expr()) -> aeso_parse_lib:parser(aeso_syntax:pat()).
 parse_pattern({app, Ann, Con = {'::', _}, Es}) ->
    {app, Ann, Con, lists:map(fun parse_pattern/1, Es)};
-parse_pattern({app, Ann, Con = {con, _, _}, Es}) ->
+parse_pattern({app, Ann, {'-', _}, [{int, _, N}]}) ->
+    {int, Ann, -N};
+parse_pattern({app, Ann, Con = {Tag, _, _}, Es}) when Tag == con; Tag == qcon ->
    {app, Ann, Con, lists:map(fun parse_pattern/1, Es)};
 parse_pattern({tuple, Ann, Es}) ->
    {tuple, Ann, lists:map(fun parse_pattern/1, Es)};
@@ -541,7 +562,10 @@ parse_pattern({list, Ann, Es}) ->
    {list, Ann, lists:map(fun parse_pattern/1, Es)};
 parse_pattern({record, Ann, Fs}) ->
    {record, Ann, lists:map(fun parse_field_pattern/1, Fs)};
+parse_pattern({typed, Ann, E, Type}) ->
+    {typed, Ann, parse_pattern(E), Type};
 parse_pattern(E = {con, _, _})    -> E;
+parse_pattern(E = {qcon, _, _})   -> E;
 parse_pattern(E = {id, _, _})     -> E;
 parse_pattern(E = {int, _, _})    -> E;
 parse_pattern(E = {bool, _, _})   -> E;
@@ -607,11 +631,28 @@ read_file(File, Opts) ->
            case maps:get(binary_to_list(File), Files, not_found) of
                not_found -> {error, not_found};
                Src       -> {ok, Src}
+            end;
+        escript ->
+            try
+                Escript        = escript:script_name(),
+                {ok, Sections} = escript:extract(Escript, []),
+                Archive        = proplists:get_value(archive, Sections),
+                FileName       = binary_to_list(filename:join([aesophia, priv, stdlib, File])),
+                case zip:extract(Archive, [{file_list, [FileName]}, memory]) of
+                    {ok, [{_, Src}]} -> {ok, Src};
+                    _                -> {error, not_found}
+                end
+            catch _:_ ->
+                {error, not_found}
            end
    end.

 stdlib_options() ->
-    [{include, {file_system, [aeso_stdlib:stdlib_include_path()]}}].
+    StdLibDir = aeso_stdlib:stdlib_include_path(),
+    case filelib:is_dir(StdLibDir) of
+        true  -> [{include, {file_system, [StdLibDir]}}];
+        false -> [{include, escript}]
+    end.

 get_include_code(File, Ann, Opts) ->
    case {read_file(File, Opts), read_file(File, stdlib_options())} of
@@ -149,6 +149,7 @@ decl({contract, _, C, Ds}) ->
    block(follow(text("contract"), hsep(name(C), text("="))), decls(Ds));
 decl({namespace, _, C, Ds}) ->
    block(follow(text("namespace"), hsep(name(C), text("="))), decls(Ds));
+decl({pragma, _, Pragma}) -> pragma(Pragma);
 decl({type_decl, _, T, Vars}) -> typedecl(alias_t, T, Vars);
 decl({type_def, _, T, Vars, Def}) ->
    Kind = element(1, Def),
@@ -168,7 +169,15 @@ decl(D = {letfun, Attrs, _, _, _, _}) ->
              false -> "function"
          end,
    hsep(lists:map(Mod, Attrs) ++ [letdecl(Fun, D)]);
-decl(D = {letval, _, _, _, _}) -> letdecl("let", D).
+decl({fun_clauses, Ann, Name, Type, Clauses}) ->
+    above([ decl(D) || D <- [{fun_decl, Ann, Name, Type} | Clauses] ]);
+decl(D = {letval, _, _, _}) -> letdecl("let", D);
+decl({block, _, Ds}) ->
+    above([ decl(D) || D <- Ds ]).
+
+-spec pragma(aeso_syntax:pragma()) -> doc().
+pragma({compiler, Op, Ver}) ->
+    text("@compiler " ++ atom_to_list(Op) ++ " " ++ string:join([integer_to_list(N) || N <- Ver], ".")).

 -spec expr(aeso_syntax:expr(), options()) -> doc().
 expr(E, Options) ->
@@ -188,10 +197,10 @@ name({tvar, _, Name})  -> text(Name);
 name({typed, _, Name, _}) -> name(Name).

 -spec letdecl(string(), aeso_syntax:letbind()) -> doc().
-letdecl(Let, {letval, _, F, T, E}) ->
-    block_expr(0, hsep([text(Let), typed(name(F), T), text("=")]), E);
+letdecl(Let, {letval, _, P, E}) ->
+    block_expr(0, hsep([text(Let), expr(P), text("=")]), E);
 letdecl(Let, {letfun, _, F, Args, T, E}) ->
-    block_expr(0, hsep([text(Let), typed(beside(name(F), args(Args)), T), text("=")]), E).
+    block_expr(0, hsep([text(Let), typed(beside(name(F), expr({tuple, [], Args})), T), text("=")]), E).

 -spec args([aeso_syntax:arg()]) -> doc().
 args(Args) ->
@@ -300,6 +309,8 @@ expr_p(_, {tuple, _, Es}) ->
    tuple(lists:map(fun expr/1, Es));
 expr_p(_, {list, _, Es}) ->
    list(lists:map(fun expr/1, Es));
+expr_p(_, {list_comp, _, E, Binds}) ->
+    list([follow(expr(E), hsep(text("|"), par(punctuate(text(","), lists:map(fun lc_bind/1, Binds)), 0)), 0)]);
 expr_p(_, {record, _, Fs}) ->
    record(lists:map(fun field/1, Fs));
 expr_p(_, {map, Ann, KVs}) ->
@@ -382,6 +393,13 @@ stmt_p({else, Else}) ->
        _ -> block_expr(200, text("else"), Else)
    end.

+lc_bind({comprehension_bind, P, E}) ->
+    follow(hsep(expr(P), text("<-")), expr(E));
+lc_bind({comprehension_if, _, E}) ->
+    beside([text("if("), expr(E), text(")")]);
+lc_bind(Let) ->
+    letdecl("let", Let).
+
 -spec bin_prec(aeso_syntax:bin_op()) -> {integer(), integer(), integer()}.
 bin_prec('..')   -> {  0,   0,   0};  %% Always printed inside '[ ]'
 bin_prec('=')    -> {  0,   0,   0};  %% Always printed inside '[ ]'
@@ -445,7 +463,7 @@ elim1(Get={map_get, _, _})    -> elim(Get);
 elim1(Get={map_get, _, _, _}) -> elim(Get).

 alt({'case', _, Pat, Body}) ->
-    block_expr(0, hsep(expr_p(500, Pat), text("=>")), Body).
+    block_expr(0, hsep(expr(Pat), text("=>")), Body).

 block_expr(_, Header, {block, _, Ss}) ->
    block(Header, statements(Ss));
@@ -455,7 +473,7 @@ block_expr(P, Header, E) ->
 statements(Stmts) ->
    above([ statement(S) || S <- Stmts ]).

-statement(S = {letval, _, _, _, _})    -> letdecl("let", S);
+statement(S = {letval, _, _, _})       -> letdecl("let", S);
 statement(S = {letfun, _, _, _, _, _}) -> letdecl("let", S);
 statement(E) -> expr(E).

@@ -13,14 +13,15 @@
                        override/2, push/2, pop/1]).

 lexer() ->
+    Number   = fun(Digit) -> [Digit, "+(_", Digit, "+)*"] end,
    DIGIT    = "[0-9]",
    HEXDIGIT = "[0-9a-fA-F]",
    LOWER    = "[a-z_]",
    UPPER    = "[A-Z]",
    CON      = [UPPER, "[a-zA-Z0-9_]*"],
-    INT      = [DIGIT, "+"],
-    HEX      = ["0x", HEXDIGIT, "+"],
-    BYTES    = ["#", HEXDIGIT, "+"],
+    INT      = Number(DIGIT),
+    HEX      = ["0x", Number(HEXDIGIT)],
+    BYTES    = ["#", Number(HEXDIGIT)],
    WS       = "[\\000-\\ ]+",
    ID       = [LOWER, "[a-zA-Z0-9_']*"],
    TVAR     = ["'", ID],
@@ -53,7 +54,7 @@ lexer() ->
        , {CHAR,   token(char,   fun parse_char/1)}
        , {STRING, token(string, fun parse_string/1)}
        , {HEX,    token(hex,    fun parse_hex/1)}
-        , {INT,    token(int,    fun list_to_integer/1)}
+        , {INT,    token(int,    fun parse_int/1)}
        , {BYTES,  token(bytes,  fun parse_bytes/1)}

          %% Identifiers (qualified first!)
@@ -95,9 +96,11 @@ parse_char([$', C, $']) -> C.

 unescape(Str) -> unescape(Str, []).

-%% TODO: numeric escapes
 unescape([$"], Acc) ->
    list_to_binary(lists:reverse(Acc));
+unescape([$\\, $x, D1, D2 | Chars ], Acc) ->
+    C = list_to_integer([D1, D2], 16),
+    unescape(Chars, [C | Acc]);
 unescape([$\\, Code | Chars], Acc) ->
    Ok = fun(C) -> unescape(Chars, [C | Acc]) end,
    case Code of
@@ -115,10 +118,18 @@ unescape([$\\, Code | Chars], Acc) ->
 unescape([C | Chars], Acc) ->
    unescape(Chars, [C | Acc]).

-parse_hex("0x" ++ Chars) -> list_to_integer(Chars, 16).
+strip_underscores(S) ->
+    lists:filter(fun(C) -> C /= $_ end, S).

-parse_bytes("#" ++ Chars) ->
-    N      = list_to_integer(Chars, 16),
-    Digits = (length(Chars) + 1) div 2,
+parse_hex("0x" ++ S) ->
+    list_to_integer(strip_underscores(S), 16).
+
+parse_int(S) ->
+    list_to_integer(strip_underscores(S)).
+
+parse_bytes("#" ++ S0) ->
+    S      = strip_underscores(S0),
+    N      = list_to_integer(S, 16),
+    Digits = (length(S) + 1) div 2,
    <<N:Digits/unit:8>>.

@@ -13,7 +13,7 @@
 -export_type([ann_line/0, ann_col/0, ann_origin/0, ann_format/0, ann/0]).
 -export_type([name/0, id/0, con/0, qid/0, qcon/0, tvar/0, op/0]).
 -export_type([bin_op/0, un_op/0]).
-export_type([decl/0, letbind/0, typedef/0]).
+-export_type([decl/0, letbind/0, typedef/0, pragma/0]).
 -export_type([arg/0, field_t/0, constructor_t/0, named_arg_t/0]).
 -export_type([type/0, constant/0, expr/0, arg_expr/0, field/1, stmt/0, alt/0, lvalue/0, elim/0, pat/0]).
 -export_type([ast/0]).
@@ -36,14 +36,21 @@

 -type decl() :: {contract, ann(), con(), [decl()]}
              | {namespace, ann(), con(), [decl()]}
+              | {pragma, ann(), pragma()}
              | {type_decl, ann(), id(), [tvar()]}
              | {type_def, ann(), id(), [tvar()], typedef()}
              | {fun_decl, ann(), id(), type()}
+              | {fun_clauses, ann(), id(), type(), [letbind()]}
+              | {block, ann(), [decl()]}
              | letbind().

+-type compiler_version() :: [non_neg_integer()].
+
+-type pragma() :: {compiler, '==' | '<' | '>' | '=<' | '>=', compiler_version()}.
+
 -type letbind()
-    :: {letval, ann(), id(), type(), expr()}
-     | {letfun, ann(), id(), [arg()], type(), expr()}.
+    :: {letval, ann(), pat(), expr()}
+     | {letfun, ann(), id(), [pat()], type(), expr()}.

 -type arg() :: {arg, ann(), id(), type()}.

@@ -95,9 +102,8 @@
     | {list, ann(), [expr()]}
     | {list_comp, ann(), expr(), [comprehension_exp()]}
     | {typed, ann(), expr(), type()}
-     | {record, ann(), [field(expr())]}
-     | {record, ann(), expr(), [field(expr())]} %% record update
-     | {map, ann(), expr(), [field(expr())]}    %% map update
+     | {record_or_map(), ann(), [field(expr())]}
+     | {record_or_map(), ann(), expr(), [field(expr())]} %% record/map update
     | {map, ann(), [{expr(), expr()}]}
     | {map_get, ann(), expr(), expr()}
     | {map_get, ann(), expr(), expr(), expr()}
@@ -106,7 +112,9 @@
     | id() | qid() | con() | qcon()
     | constant().

-type comprehension_exp() :: [ {comprehension_bind, id(), expr()}
+-type record_or_map() :: record | map | record_or_map_error.
+
+-type comprehension_exp() :: [ {comprehension_bind, pat(), expr()}
                             | {comprehension_if, ann(), expr()}
                             | letbind() ].

@@ -134,6 +142,7 @@
 -type pat() :: {app, ann(), con() | op(), [pat()]}
             | {tuple, ann(), [pat()]}
             | {list, ann(), [pat()]}
+             | {typed, ann(), pat(), type()}
             | {record, ann(), [field(pat())]}
             | constant()
             | con()
@@ -48,8 +48,9 @@ fold(Alg = #alg{zero = Zero, plus = Plus, scoped = Scoped}, Fun, K, X) ->
            {type_decl, _, I, _}     -> BindType(I);
            {type_def, _, I, _, D}   -> Plus(BindType(I), Decl(D));
            {fun_decl, _, _, T}      -> Type(T);
-            {letval, _, F, T, E}     -> Sum([BindExpr(F), Type(T), Expr(E)]);
+            {letval, _, P, E}        -> Scoped(BindExpr(P), Expr(E));
            {letfun, _, F, Xs, T, E} -> Sum([BindExpr(F), Type(T), Expr(Xs ++ [E])]);
+            {fun_clauses, _, _, T, Cs} -> Sum([Type(T) | [Decl(C) || C <- Cs]]);
            %% typedef()
            {alias_t, T}    -> Type(T);
            {record_t, Fs}  -> Type(Fs);
@@ -76,8 +77,8 @@ fold(Alg = #alg{zero = Zero, plus = Plus, scoped = Scoped}, Fun, K, X) ->
                Plus(Expr(E), Scoped(BindExpr(I), Expr({list_comp, A, Y, R})));
            {list_comp, A, Y, [{comprehension_if, _, E}|R]} ->
                Plus(Expr(E), Expr({list_comp, A, Y, R}));
-            {list_comp, A, Y, [D = {letval, _, F, _, _} | R]} ->
-                Plus(Decl(D), Scoped(BindExpr(F), Expr({list_comp, A, Y, R})));
+            {list_comp, A, Y, [D = {letval, _, Pat, _} | R]} ->
+                Plus(Decl(D), Scoped(BindExpr(Pat), Expr({list_comp, A, Y, R})));
            {list_comp, A, Y, [D = {letfun, _, F, _, _, _} | R]} ->
                Plus(Decl(D), Scoped(BindExpr(F), Expr({list_comp, A, Y, R})));
            {typed, _, E, T}       -> Plus(Expr(E), Type(T));
@@ -18,8 +18,13 @@ from_aevm(word, {id, _, "address"},                     N) -> address_literal(ac
 from_aevm(word, {app_t, _, {id, _, "oracle"}, _},       N) -> address_literal(oracle_pubkey, N);
 from_aevm(word, {app_t, _, {id, _, "oracle_query"}, _}, N) -> address_literal(oracle_query_id, N);
 from_aevm(word, {con, _, _Name},                        N) -> address_literal(contract_pubkey, N);
-from_aevm(word, {id, _, "int"},     N) -> <<N1:256/signed>> = <<N:256>>, {int, [], N1};
-from_aevm(word, {id, _, "bits"},    N) -> error({todo, bits, N});
+from_aevm(word, {id, _, "int"}, N0) ->
+    <<N:256/signed>> = <<N0:256>>,
+    if N < 0 -> {app, [{format, prefix}], {'-', []}, [{int, [], -N}]};
+       true  -> {int, [], N} end;
+from_aevm(word, {id, _, "bits"}, N0) ->
+    <<N:256/signed>> = <<N0:256>>,
+    make_bits(N);
 from_aevm(word, {id, _, "bool"}, N) -> {bool, [], N /= 0};
 from_aevm(word, {bytes_t, _, Len}, Val) when Len =< 32 ->
    <<Bytes:Len/unit:8, _/binary>> = <<Val:32/unit:8>>,
@@ -55,6 +60,7 @@ from_aevm({variant, VmCons}, {variant_t, Cons}, {variant, Tag, Args})
    VmTypes = lists:nth(Tag + 1, VmCons),
    ConType = lists:nth(Tag + 1, Cons),
    from_aevm(VmTypes, ConType, Args);
+from_aevm([], {constr_t, _, Con, []}, []) -> Con;
 from_aevm(VmTypes, {constr_t, _, Con, Types}, Args)
        when length(VmTypes) == length(Types),
             length(VmTypes) == length(Args) ->
@@ -70,8 +76,10 @@ from_fate({app_t, _, {id, _, "oracle"}, _}, ?FATE_ORACLE(Bin)) -> {oracle_pubkey
 from_fate({app_t, _, {id, _, "oracle_query"}, _}, ?FATE_ORACLE_Q(Bin)) -> {oracle_query_id, [], Bin};
 from_fate({con, _, _Name},  ?FATE_CONTRACT(Bin)) -> {contract_pubkey, [], Bin};
 from_fate({bytes_t, _, N},  ?FATE_BYTES(Bin)) when byte_size(Bin) == N -> {bytes, [], Bin};
-from_fate({id, _, "bits"},  ?FATE_BITS(Bin)) -> error({todo, bits, Bin});
-from_fate({id, _, "int"},     N) when is_integer(N) -> {int, [], N};
+from_fate({id, _, "bits"},  ?FATE_BITS(N)) -> make_bits(N);
+from_fate({id, _, "int"},     N) when is_integer(N) ->
+    if N < 0 -> {app, [{format, prefix}], {'-', []}, [{int, [], -N}]};
+       true  -> {int, [], N} end;
 from_fate({id, _, "bool"},    B) when is_boolean(B) -> {bool, [], B};
 from_fate({id, _, "string"}, S) when is_binary(S) -> {string, [], S};
 from_fate({app_t, _, {id, _, "list"}, [Type]}, List) when is_list(List) ->
@@ -105,9 +113,23 @@ from_fate({variant_t, Cons}, {variant, Ar, Tag, Args})
            from_fate(ConType, ArgList);
        _ -> throw(cannot_translate_to_sophia)
    end;
+from_fate({constr_t, _, Con, []}, []) -> Con;
 from_fate({constr_t, _, Con, Types}, Args)
        when length(Types) == length(Args) ->
    {app, [], Con, [ from_fate(Type, Arg)
                     || {Type, Arg} <- lists:zip(Types, Args) ]};
 from_fate(_Type, _Data) ->
    throw(cannot_translate_to_sophia).
+
+
+make_bits(N) ->
+    Id = fun(F) -> {qid, [], ["Bits", F]} end,
+    if N < 0 -> make_bits(Id("clear"), Id("all"), 0, bnot N);
+       true  -> make_bits(Id("set"), Id("none"), 0, N) end.
+
+make_bits(_Set, Zero, _I, 0) -> Zero;
+make_bits(Set, Zero, I, N) when 0 == N rem 2 ->
+    make_bits(Set, Zero, I + 1, N div 2);
+make_bits(Set, Zero, I, N) ->
+    {app, [], Set, [make_bits(Set, Zero, I + 1, N div 2), {int, [], I}]}.
+
@@ -1,6 +1,6 @@
 {application, aesophia,
 [{description, "Contract Language for aeternity"},
-  {vsn, "4.0.0-rc3"},
+  {vsn, "4.2.0"},
  {registered, []},
  {applications,
   [kernel,
@@ -62,7 +62,7 @@ encode_decode_sophia_test() ->
                                Other -> Other
                              end end,
    ok = Check("int", "42"),
-    ok = Check("int", "-42"),
+    ok = Check("int", "- 42"),
    ok = Check("bool", "true"),
    ok = Check("bool", "false"),
    ok = Check("string", "\"Hello\""),
@@ -106,7 +106,7 @@ aci_test_contract(Name) ->
    ok.

 check_stub(Stub, Options) ->
-    case aeso_parser:string(binary_to_list(Stub), Options) of
+    try aeso_parser:string(binary_to_list(Stub), Options) of
        Ast ->
            try
                %% io:format("AST: ~120p\n", [Ast]),
@@ -117,9 +117,9 @@ check_stub(Stub, Options) ->
                  _:R ->
                io:format("Error: ~p\n", [R]),
                error(R)
-            end;
-        {error, E} ->
-            io:format("Error: ~p\n", [E]),
-            error({parse_error, E})
+            end
+    catch throw:{error, Errs} ->
+        _ = [ io:format("~s\n", [aeso_errors:pp(E)]) || E <- Errs ],
+        error({parse_errors, Errs})
    end.

@@ -29,11 +29,10 @@ calldata_test_() ->
                  true -> ast_exprs(ContractString, Fun, Args, [{backend, fate}]);
                  false -> undefined
              end,
-           case FateExprs == undefined orelse AevmExprs == undefined of
-               true -> ok;
-               false ->
-                   ?assertEqual(FateExprs, AevmExprs)
-           end
+           ParsedExprs = parse_args(Fun, Args),
+           [ ?assertEqual(ParsedExprs, AevmExprs) || AevmExprs /= undefined ],
+           [ ?assertEqual(ParsedExprs, FateExprs) || FateExprs /= undefined ],
+           ok
        end} || {ContractName, Fun, Args} <- compilable_contracts()].

 calldata_aci_test_() ->
@@ -53,19 +52,34 @@ calldata_aci_test_() ->
                  true -> ast_exprs(ContractACI, Fun, Args, [{backend, fate}]);
                  false -> undefined
              end,
-           case FateExprs == undefined orelse AevmExprs == undefined of
-               true -> ok;
-               false ->
-                   ?assertEqual(FateExprs, AevmExprs)
-           end
+           ParsedExprs = parse_args(Fun, Args),
+           [ ?assertEqual(ParsedExprs, AevmExprs) || AevmExprs /= undefined ],
+           [ ?assertEqual(ParsedExprs, FateExprs) || FateExprs /= undefined ],
+           ok
        end} || {ContractName, Fun, Args} <- compilable_contracts()].

+parse_args(Fun, Args) ->
+    [{contract, _, _, [{letfun, _, _, _, _, {app, _, _, AST}}]}] =
+        aeso_parser:string("contract Temp = function foo() = " ++ Fun ++ "(" ++ string:join(Args, ", ") ++ ")"),
+    strip_ann(AST).
+
+strip_ann(T) when is_tuple(T) ->
+    strip_ann1(setelement(2, T, []));
+strip_ann(X) -> strip_ann1(X).
+
+strip_ann1({map, [], KVs}) ->
+    {map, [], [{strip_ann(K), strip_ann(V)} || {K, V} <- KVs]};
+strip_ann1(T) when is_tuple(T) ->
+    list_to_tuple(strip_ann1(tuple_to_list(T)));
+strip_ann1(L) when is_list(L) ->
+    lists:map(fun strip_ann/1, L);
+strip_ann1(X) -> X.

 ast_exprs(ContractString, Fun, Args, Opts) ->
    {ok, Data} = (catch aeso_compiler:create_calldata(ContractString, Fun, Args, Opts)),
    {ok, _Types, Exprs} = (catch aeso_compiler:decode_calldata(ContractString, Fun, Data, Opts)),
    ?assert(is_list(Exprs)),
-    Exprs.
+    strip_ann(Exprs).

 check_errors(Expect, ErrorString) ->
    %% This removes the final single \n as well.
@@ -85,7 +99,9 @@ compilable_contracts() ->
     {"maps", "init", []},
     {"funargs", "menot", ["false"]},
     {"funargs", "append", ["[\"false\", \" is\", \" not\", \" true\"]"]},
-     %% TODO {"funargs", "bitsum", ["Bits.all"]},
+     {"funargs", "bitsum", ["Bits.all"]},
+     {"funargs", "bitsum", ["Bits.clear(Bits.clear(Bits.all, 4), 2)"]}, %% Order matters for test
+     {"funargs", "bitsum", ["Bits.set(Bits.set(Bits.none, 4), 2)"]},
     {"funargs", "read", ["{label = \"question 1\", result = 4}"]},
     {"funargs", "sjutton", ["#0011012003100011012003100011012003"]},
     {"funargs", "sextiosju", ["#01020304050607080910111213141516171819202122232425262728293031323334353637383940"
@@ -12,6 +12,14 @@

 -include_lib("eunit/include/eunit.hrl").

+run_test(Test) ->
+    TestFun = list_to_atom(lists:concat([Test, "_test_"])),
+    [ begin
+          io:format("~s\n", [Label]),
+          Fun()
+      end || {Label, Fun} <- ?MODULE:TestFun() ],
+    ok.
+
 %%  Very simply test compile the given contracts. Only basic checks
 %%  are made on the output, just that it is a binary which indicates
 %%  that the compilation worked.
@@ -130,6 +138,7 @@ compilable_contracts() ->
     "test",
     "builtin_bug",
     "builtin_map_get_bug",
+     "lc_record_bug",
     "nodeadcode",
     "deadcode",
     "variant_types",
@@ -152,7 +161,11 @@ compilable_contracts() ->
     "manual_stdlib_include",
     "list_comp",
     "payable",
-     "unapplied_builtins"
+     "unapplied_builtins",
+     "underscore_number_literals",
+     "qualified_constructor",
+     "let_patterns",
+     "lhs_matching"
    ].

 not_yet_compilable(fate) -> [];
@@ -175,6 +188,8 @@ not_yet_compilable(aevm) -> [].
 -define(PARSE_ERROR(Name, Errs), ?ERROR("Parse", Name, Errs)).

 failing_contracts() ->
+    {ok, V} = aeso_compiler:numeric_version(),
+    Version = list_to_binary(string:join([integer_to_list(N) || N <- V], ".")),
    %% Parse errors
    [ ?PARSE_ERROR(field_parse_error,
       [<<?Pos(5, 26)
@@ -285,9 +300,22 @@ failing_contracts() ->
          "Repeated name x in pattern\n"
          "  x :: x (at line 26, column 7)">>,
        <<?Pos(44, 14)
-          "Repeated argument x to function repeated_arg (at line 44, column 14).">>,
-        <<?Pos(44, 14)
-          "Repeated argument y to function repeated_arg (at line 44, column 14).">>,
+          "Repeated names x, y in pattern\n"
+          "  (x : int, y, x : string, y : bool) (at line 44, column 14)">>,
+        <<?Pos(44, 39)
+          "Cannot unify int\n"
+          "         and string\n"
+          "when checking the type of the expression at line 44, column 39\n"
+          "  x : int\n"
+          "against the expected type\n"
+          "  string">>,
+        <<?Pos(44, 72)
+          "Cannot unify int\n"
+          "         and string\n"
+          "when checking the type of the expression at line 44, column 72\n"
+          "  x : int\n"
+          "against the expected type\n"
+          "  string">>,
        <<?Pos(14, 24)
          "No record type with fields y, z (at line 14, column 24)">>,
        <<?Pos(15, 26)
@@ -301,7 +329,14 @@ failing_contracts() ->
        <<?Pos(54, 5)
          "Let binding at line 54, column 5 must be followed by an expression">>,
        <<?Pos(58, 5)
-          "Let binding at line 58, column 5 must be followed by an expression">>])
+          "Let binding at line 58, column 5 must be followed by an expression">>,
+        <<?Pos(63, 5)
+          "Cannot unify int\n"
+          "         and bool\n"
+          "when checking the type of the expression at line 63, column 5\n"
+          "  id(n) : int\n"
+          "against the expected type\n"
+          "  bool">>])
    , ?TYPE_ERROR(init_type_error,
       [<<?Pos(7, 3)
          "Cannot unify string\n"
@@ -346,73 +381,7 @@ failing_contracts() ->
         <<?Pos(3, 13)
           "Nested namespace not allowed\nNamespace 'Foo' at line 3, column 13 not defined at top level.">>])
    , ?TYPE_ERROR(bad_address_literals,
-        [<<?Pos(32, 5)
-           "The type bytes(32) is not a contract type\n"
-           "when checking that the contract literal at line 32, column 5\n"
-           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
-           "has the type\n"
-           "  bytes(32)">>,
-         <<?Pos(30, 5)
-           "The type oracle(int, bool) is not a contract type\n"
-           "when checking that the contract literal at line 30, column 5\n"
-           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
-           "has the type\n"
-           "  oracle(int, bool)">>,
-         <<?Pos(28, 5)
-           "The type address is not a contract type\n"
-           "when checking that the contract literal at line 28, column 5\n"
-           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
-           "has the type\n"
-           "  address">>,
-         <<?Pos(25, 5)
-           "Cannot unify oracle_query('a, 'b)\n"
-           "         and Remote\n"
-           "when checking the type of the expression at line 25, column 5\n"
-           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
-           "    oracle_query('a, 'b)\n"
-           "against the expected type\n"
-           "  Remote">>,
-         <<?Pos(23, 5)
-           "Cannot unify oracle_query('c, 'd)\n"
-           "         and bytes(32)\n"
-           "when checking the type of the expression at line 23, column 5\n"
-           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
-           "    oracle_query('c, 'd)\n"
-           "against the expected type\n"
-           "  bytes(32)">>,
-         <<?Pos(21, 5)
-           "Cannot unify oracle_query('e, 'f)\n"
-           "         and oracle(int, bool)\n"
-           "when checking the type of the expression at line 21, column 5\n"
-           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
-           "    oracle_query('e, 'f)\n"
-           "against the expected type\n"
-           "  oracle(int, bool)">>,
-         <<?Pos(18, 5)
-           "Cannot unify oracle('g, 'h)\n"
-           "         and Remote\n"
-           "when checking the type of the expression at line 18, column 5\n"
-           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
-           "    oracle('g, 'h)\n"
-           "against the expected type\n"
-           "  Remote">>,
-         <<?Pos(16, 5)
-           "Cannot unify oracle('i, 'j)\n"
-           "         and bytes(32)\n"
-           "when checking the type of the expression at line 16, column 5\n"
-           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
-           "    oracle('i, 'j)\n"
-           "against the expected type\n"
-           "  bytes(32)">>,
-         <<?Pos(14, 5)
-           "Cannot unify oracle('k, 'l)\n"
-           "         and oracle_query(int, bool)\n"
-           "when checking the type of the expression at line 14, column 5\n"
-           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
-           "    oracle('k, 'l)\n"
-           "against the expected type\n"
-           "  oracle_query(int, bool)">>,
-         <<?Pos(11, 5)
+        [<<?Pos(11, 5)
           "Cannot unify address\n"
           "         and oracle(int, bool)\n"
           "when checking the type of the expression at line 11, column 5\n"
@@ -432,7 +401,79 @@ failing_contracts() ->
           "when checking the type of the expression at line 7, column 5\n"
           "  ak_2gx9MEFxKvY9vMG5YnqnXWv1hCsX7rgnfvBLJS4aQurustR1rt : address\n"
           "against the expected type\n"
-           "  bytes(32)">>])
+           "  bytes(32)">>,
+         <<?Pos(14, 5)
+           "Cannot unify oracle('a, 'b)\n"
+           "         and oracle_query(int, bool)\n"
+           "when checking the type of the expression at line 14, column 5\n"
+           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
+           "    oracle('a, 'b)\n"
+           "against the expected type\n"
+           "  oracle_query(int, bool)">>,
+         <<?Pos(16, 5)
+           "Cannot unify oracle('c, 'd)\n"
+           "         and bytes(32)\n"
+           "when checking the type of the expression at line 16, column 5\n"
+           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
+           "    oracle('c, 'd)\n"
+           "against the expected type\n"
+           "  bytes(32)">>,
+         <<?Pos(18, 5)
+           "Cannot unify oracle('e, 'f)\n"
+           "         and Remote\n"
+           "when checking the type of the expression at line 18, column 5\n"
+           "  ok_2YNyxd6TRJPNrTcEDCe9ra59SVUdp9FR9qWC5msKZWYD9bP9z5 :\n"
+           "    oracle('e, 'f)\n"
+           "against the expected type\n"
+           "  Remote">>,
+         <<?Pos(21, 5)
+           "Cannot unify oracle_query('g, 'h)\n"
+           "         and oracle(int, bool)\n"
+           "when checking the type of the expression at line 21, column 5\n"
+           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
+           "    oracle_query('g, 'h)\n"
+           "against the expected type\n"
+           "  oracle(int, bool)">>,
+         <<?Pos(23, 5)
+           "Cannot unify oracle_query('i, 'j)\n"
+           "         and bytes(32)\n"
+           "when checking the type of the expression at line 23, column 5\n"
+           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
+           "    oracle_query('i, 'j)\n"
+           "against the expected type\n"
+           "  bytes(32)">>,
+         <<?Pos(25, 5)
+           "Cannot unify oracle_query('k, 'l)\n"
+           "         and Remote\n"
+           "when checking the type of the expression at line 25, column 5\n"
+           "  oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY :\n"
+           "    oracle_query('k, 'l)\n"
+           "against the expected type\n"
+           "  Remote">>,
+         <<?Pos(28, 5)
+           "The type address is not a contract type\n"
+           "when checking that the contract literal\n"
+           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
+           "has the type\n"
+           "  address">>,
+         <<?Pos(30, 5)
+           "The type oracle(int, bool) is not a contract type\n"
+           "when checking that the contract literal\n"
+           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
+           "has the type\n"
+           "  oracle(int, bool)">>,
+         <<?Pos(32, 5)
+           "The type bytes(32) is not a contract type\n"
+           "when checking that the contract literal\n"
+           "  ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ\n"
+           "has the type\n"
+           "  bytes(32)">>,
+         <<?Pos(34, 5),
+           "The type address is not a contract type\n"
+           "when checking that the call to\n"
+           "  Address.to_contract\n"
+           "has the type\n"
+           "  address">>])
    , ?TYPE_ERROR(stateful,
       [<<?Pos(13, 35)
          "Cannot reference stateful function Chain.spend (at line 13, column 35)\nin the definition of non-stateful function fail1.">>,
@@ -542,7 +583,7 @@ failing_contracts() ->
            "Failed to resolve byte array lengths in call to Bytes.split with argument of type\n"
            "  - 'f  (at line 12, column 20)\n"
            "and result types\n"
-            "  - 'e  (at line 13, column 5)\n"
+            "  - 'e  (at line 12, column 25)\n"
            "  - bytes(20)  (at line 12, column 29)">>,
          <<?Pos(16, 5)
            "Failed to resolve byte array lengths in call to Bytes.split with argument of type\n"
@@ -555,7 +596,33 @@ failing_contracts() ->
            "  - 'b  (at line 18, column 20)\n"
            "and result types\n"
            "  - bytes(20)  (at line 18, column 25)\n"
-            "  - 'a  (at line 19, column 5)">>])
+            "  - 'a  (at line 18, column 37)">>])
+    , ?TYPE_ERROR(wrong_compiler_version,
+        [<<?Pos(1, 1)
+           "Cannot compile with this version of the compiler,\n"
+           "because it does not satisfy the constraint ", Version/binary, " < 1.0">>,
+         <<?Pos(2, 1)
+           "Cannot compile with this version of the compiler,\n"
+           "because it does not satisfy the constraint ", Version/binary, " == 9.9.9">>])
+    , ?TYPE_ERROR(multiple_contracts,
+         [<<?Pos(2, 3)
+            "Only the main contract can contain defined functions or entrypoints.\n"
+            "Fix: replace the definition of 'foo' by a type signature.">>])
+    , ?TYPE_ERROR(contract_as_namespace,
+         [<<?Pos(5, 28)
+            "Invalid call to contract entrypoint 'Foo.foo'.\n"
+            "It must be called as 'c.foo' for some c : Foo.">>])
+    , ?TYPE_ERROR(bad_records,
+        [<<?Pos(3, 16)
+           "Mixed record fields and map keys in\n"
+           "  {x = 0, [0] = 1}">>,
+         <<?Pos(4, 6)
+           "Mixed record fields and map keys in\n"
+           "  r {x = 0, [0] = 1}">>,
+         <<?Pos(5, 6)
+           "Empty record/map update\n"
+           "  r {}">>
+        ])
    ].

 -define(Path(File), "code_errors/" ??File).
@@ -671,3 +738,44 @@ failing_code_gen_contracts() ->
            "The state cannot contain functions in the AEVM. Use FATE if you need this.")
    ].

+validation_test_() ->
+    [{"Validation fail: " ++ C1 ++ " /= " ++ C2,
+      fun() ->
+        Actual = case validate(C1, C2) of
+                    {error, Errs} -> Errs;
+                    ok -> #{}
+                 end,
+        check_errors(Expect, Actual)
+      end} || {C1, C2, Expect} <- validation_fails()] ++
+    [{"Validation of " ++ C,
+      fun() ->
+        ?assertEqual(ok, validate(C, C))
+      end} || C <- compilable_contracts()].
+
+validation_fails() ->
+    [{"deadcode", "nodeadcode",
+      [<<"Data error:\n"
+         "Byte code does not match source code.\n"
+         "- Functions in the source code but not in the byte code:\n"
+         "    .MyList.map2">>]},
+     {"validation_test1", "validation_test2",
+      [<<"Data error:\n"
+         "Byte code does not match source code.\n"
+         "- The implementation of the function code_fail is different.\n"
+         "- The attributes of the function attr_fail differ:\n"
+         "    Byte code:   payable\n"
+         "    Source code: \n"
+         "- The type of the function type_fail differs:\n"
+         "    Byte code:   integer => integer\n"
+         "    Source code: {tvar,0} => {tvar,0}">>]},
+     {"validation_test1", "validation_test3",
+      [<<"Data error:\n"
+         "Byte code contract is not payable, but source code contract is.">>]}].
+
+validate(Contract1, Contract2) ->
+    ByteCode = #{ fate_code := FCode } = compile(fate, Contract1),
+    FCode1   = aeb_fate_code:serialize(aeb_fate_code:strip_init_function(FCode)),
+    Source   = aeso_test_utils:read_contract(Contract2),
+    aeso_compiler:validate_byte_code(ByteCode#{ byte_code := FCode1 }, Source,
+                                     [{backend, fate}, {include, {file_system, [aeso_test_utils:contract_path()]}}]).
+
@@ -4,6 +4,8 @@

 -include_lib("eunit/include/eunit.hrl").

+id(X) -> X.
+
 simple_contracts_test_() ->
    {foreach,
     fun() -> ok end,
@@ -14,7 +16,7 @@ simple_contracts_test_() ->
                   "  function id(x) = x\n",
            ?assertMatch(
                [{contract, _, {con, _, "Identity"},
-                    [{letfun, _, {id, _, "id"}, [{arg, _, {id, _, "x"}, {id, _, "_"}}], {id, _, "_"},
+                    [{letfun, _, {id, _, "id"}, [{id, _, "x"}], {id, _, "_"},
                        {id, _, "x"}}]}], parse_string(Text)),
            ok
       end},
@@ -30,7 +32,7 @@ simple_contracts_test_() ->
                    end,
            Parse = fun(S) ->
                    try remove_line_numbers(parse_expr(S))
-                    catch _:_ -> ?assertMatch(ok, {parse_fail, S}) end
+                    catch _:_ -> ?assertMatch(ok, id({parse_fail, S})) end
                end,
            CheckParens = fun(Expr) ->
                    ?assertEqual(Parse(NoPar(Expr)), Parse(Par(Expr)))
@@ -38,7 +40,6 @@ simple_contracts_test_() ->
            LeftAssoc  = fun(Op) -> CheckParens({{a, Op, b}, Op, c}) end,
            RightAssoc = fun(Op) -> CheckParens({a, Op, {b, Op, c}}) end,
            NonAssoc   = fun(Op) ->
-                            OpAtom = list_to_atom(Op),
                            ?assertThrow({error, [_]},
                                         parse_expr(NoPar({a, Op, {b, Op, c}}))) end,
            Stronger = fun(Op1, Op2) ->
@@ -77,7 +78,7 @@ parse_string(Text, Opts) ->
    aeso_parser:string(Text, Opts).

 parse_expr(Text) ->
-    [{letval, _, _, _, Expr}] =
+    [{letval, _, _, Expr}] =
        parse_string("let _ = " ++ Text),
    Expr.

@@ -11,4 +11,6 @@ contract AddressLiterals =
    oq_2oRvyowJuJnEkxy58Ckkw77XfWJrmRgmGaLzhdqb67SKEL1gPY
  entrypoint contr() : Remote =
    ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ
+  entrypoint contr_addr() : Remote =
+    Address.to_contract(addr())

@@ -30,4 +30,6 @@ contract AddressLiterals =
    ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ
  entrypoint contr3() : bytes(32) =
    ct_Ez6MyeTMm17YnTnDdHTSrzMEBKmy7Uz2sXu347bTDPgVH2ifJ
+  entrypoint contr4() : address =
+    Address.to_contract(Contract.address)

@@ -0,0 +1,5 @@
+contract BadRecord =
+  entrypoint foo() =
+    let r = {x = 0, [0] = 1}
+    r{x = 0, [0] = 1}
+    r{}
@@ -15,3 +15,5 @@ contract BasicAuth =
  entrypoint to_sign(h : hash, n : int) =
    Crypto.blake2b((h, n))

+  entrypoint weird_string() : string =
+    "\x19Weird String\x42\nMore\n"
@@ -0,0 +1,6 @@
+contract Foo =
+  entrypoint foo : () => int
+
+contract Fail =
+  entrypoint bad() : int = Foo.foo()
+
@@ -11,7 +11,7 @@ contract Factorial =

  stateful entrypoint set_worker(worker) = put(state{worker = worker})

-  entrypoint fac(x : int) : int =
-    if(x == 0) 1
-    else x * state.worker.fac(x - 1)
-
+  entrypoint
+    fac : int => int
+    fac(0) = 1
+    fac(x) = x * state.worker.fac(x - 1)
@@ -0,0 +1,4 @@
+contract Foo =
+  record r = {x : int}
+  // Crashed in the backend due to missing type annotation on the lc body.
+  entrypoint lc(xs) = [ {x = x} | x <- xs ]
@@ -0,0 +1,15 @@
+contract LetPatterns =
+
+  record r = {x : int, y : int, b : bool}
+
+  entrypoint test() = foo([1, 0], (2, 3), Some(4), {x = 5, y = 6, b = false})
+
+  entrypoint foo(xs : list(int), p : int * int, some : option(int), r : r) =
+    let x :: _  = xs
+    let (a, b)  = p
+    let Some(n) = some
+    let {x = i, y = j} = r
+    x + a + b + n + i + j
+
+  entrypoint lc(xs : list(option(int))) : list(int) =
+    [ x | Some(x) <- xs ]
@@ -0,0 +1,22 @@
+contract LHSMatching =
+
+  function from_some(Some(x)) = x
+
+  function
+    length : list('a) => int
+    length([])      = 0
+    length(_ :: xs) = 1 + length(xs)
+
+  function
+    append([], ys)      = ys
+    append(x :: xs, ys) = x :: append(xs, ys)
+
+  function local_match(xs : list('a)) =
+    let null([])     = true
+    let null(_ :: _) = false
+    !null(xs)
+
+  entrypoint main() =
+    from_some(Some([0]))
+      ++ append([length([true]), 2, 3], [4, 5, 6])
+      ++ [7 | if (local_match([false]))]
@@ -0,0 +1,5 @@
+contract ContractOne =
+  entrypoint foo() = "foo"
+
+contract ContractTwo =
+  entrypoint bar() = "bar"
@@ -0,0 +1,8 @@
+namespace Foo =
+  datatype x = A | B(int)
+
+contract Bar =
+  entrypoint f(a : Foo.x) =
+    switch(a)
+      Foo.A     => 0
+      Foo.B(n)  => n
@@ -8,10 +8,9 @@ contract Stack =

  entrypoint init(ss : list(string)) = { stack = ss, size = length(ss) }

-  function length(xs) =
-    switch(xs)
-      [] => 0
-      _ :: xs => length(xs) + 1
+  function
+    length([])      = 0
+    length(_ :: xs) = length(xs) + 1

  stateful entrypoint pop() : string =
    switch(state.stack)
@@ -57,3 +57,8 @@ contract Test =
    let f() = 0
    let g() = f()

+  function id(x : 'a) : 'a = x
+
+  entrypoint wrong_return(n : int) : bool =
+    id(n)
+
@@ -0,0 +1,13 @@
+
+contract UnderscoreNumberLiterals =
+
+  entrypoint ints() : list(int) =
+    [ 1_999_000_000,
+      19_99_00_00_00,
+      0xfff_FFF_010 ]
+
+  entrypoint bytes() : list(bytes(4)) =
+    [ #abcd_ef_00,
+      #01_02_03_04,
+      #aaaa_FFFF ]
+
@@ -0,0 +1,4 @@
+contract ValidationTest =
+  payable entrypoint attr_fail() = ()
+  entrypoint type_fail(x : int) = x
+  entrypoint code_fail(x) = x + 1
@@ -0,0 +1,4 @@
+contract ValidationTest =
+  entrypoint attr_fail() = ()
+  entrypoint type_fail(x) = x
+  entrypoint code_fail(x) = x - 1
@@ -0,0 +1,4 @@
+payable contract ValidationTest =
+  payable entrypoint attr_fail() = ()
+  entrypoint type_fail(x : int) = x
+  entrypoint code_fail(x) = x + 1
@@ -0,0 +1,7 @@
+@compiler < 1.0
+@compiler == 9.9.9
+@compiler >= 0.1
+@compiler =< 100.0.1
+
+contract Fail =
+  entrypoint foo() = ()
Author	SHA1	Message	Date
Hans Svensson	efd45df820	Merge pull request #212 from aeternity/GH-211-prepare_release_4_2_0 Prepare release 4.2.0	2020-01-15 11:58:47 +01:00
Hans Svensson	a6f51d23f3	Bump version to 4.2.0 and fix CHANGELOG	2020-01-15 11:39:25 +01:00
Ulf Norell	4d4a14a9ab	GH-196 pattern matching lhs (#210 ) * Allow block with separate type signature and definition of a function For instance, ``` function add : (int, int) => int add(x, y) = x + y ``` cc #196 * Allow pattern matching in left-hand sides * Changelog * Fix type spec * partial case-on-constructor * Changelog for pattern-matching lets	2020-01-15 09:41:03 +01:00
Ulf Norell	f7abaf07fa	Add list comprehension match to test case	2019-12-16 17:04:49 +01:00
Ulf Norell	d019e44924	Compile values to immediates when possible	2019-12-16 17:04:49 +01:00
Ulf Norell	ad54134961	Parse negative literal patterns	2019-12-16 17:04:49 +01:00
Ulf Norell	b51a79b5e1	Allow patterns in lets and list comprehension binds	2019-12-16 17:04:49 +01:00
Ulf Norell	d844c4d276	Fix missing type annotation in list comprehension body	2019-12-12 09:39:13 +01:00
Ulf Norell	64e2fff91a	Handle list comprehensions in pretty printer	2019-12-12 09:39:13 +01:00
Ulf Norell	d4f291f252	Handle qualified constructors in patterns	2019-12-12 09:34:26 +01:00
Ulf Norell	b9f585ebaf	Merge pull request #205 from aeternity/fate-flatten-store FATE backend optimisations	2019-12-12 09:22:37 +01:00
Ulf Norell	954af13f59	Fix debug printing of store registers	2019-12-12 09:14:34 +01:00
Ulf Norell	2e4558b3b4	Changelog	2019-12-10 12:57:52 +01:00
Ulf Norell	a403a9d227	Unbox singleton tuples and records	2019-12-10 12:24:05 +01:00
Ulf Norell	c7b846cbfe	Merge pull request #190 from aeternity/GH-189-parse-error-crash Fix parse errors causing crashes instead of nice errors	2019-12-09 10:27:20 +01:00
Ulf Norell	bf5e2e2443	Fix parse errors causing crashes instead of nice errors	2019-12-09 08:45:55 +01:00
Ulf Norell	46a30b118f	Get rid of unnecessary return instruction after tail-call	2019-11-26 13:33:11 +01:00
Ulf Norell	bb1a45c557	Improve case-on-constructor optimisation	2019-11-26 13:10:58 +01:00
Ulf Norell	0a22c7a34a	More let-floating	2019-11-26 13:10:58 +01:00
Ulf Norell	c8153f94a6	More aggressive freshening to avoid shadowing issues	2019-11-26 13:10:58 +01:00
Ulf Norell	63d51baaa3	Dialyzer issues	2019-11-26 13:10:58 +01:00
Ulf Norell	cb045b0256	whitespace	2019-11-26 13:10:58 +01:00
Ulf Norell	c84064da7f	Inline local functions and simplify case-on-constructor	2019-11-26 13:10:58 +01:00
Ulf Norell	ad88797cef	Proper handling of lets in term_to_fate	2019-11-26 13:10:58 +01:00
Ulf Norell	6c3932b10c	Flattened state layout ... with necessary optimizations.	2019-11-26 13:10:56 +01:00
Ulf Norell	8d7c637241	Don't confuse variables and store registers in fate asm generation	2019-11-26 13:10:04 +01:00
Ulf Norell	a8119f1219	Track state layout ... but only default layout still.	2019-11-26 13:10:04 +01:00
Ulf Norell	d0fdd06d66	Change get_state and set_state fcode primitives to take a register	2019-11-26 13:10:04 +01:00
Ulf Norell	99ecda4b7b	Fix warnings in test suites	2019-11-26 13:10:04 +01:00
Ulf Norell	e645a8d034	Optimize before lambda lifting (lambdas are either in dead code or not dead, so dead code elimination won't be affected)	2019-11-26 13:10:04 +01:00
Ulf Norell	499e2f8200	Handle records and type aliases correctly in fcode	2019-11-26 13:10:04 +01:00
Ulf Norell	5465b74ac9	Allow specifying store register in FATE backend	2019-11-26 13:10:04 +01:00
Hans Svensson	6ca63e4b40	Merge pull request #184 from aeternity/GH-181-prepare-4.1.0 Bump version to 4.1.0	2019-11-26 09:02:56 +01:00
Ulf Norell	08b6148223	Bump version to 4.1.0	2019-11-26 09:02:26 +01:00
Ulf Norell	8a47603b62	Merge pull request #182 from aeternity/GH-181-prepare-4.1.0-rc1 GH-181 Prepare 4.1.0-rc1	2019-11-25 12:16:03 +01:00
Ulf Norell	d4c9d369b1	Remove aesophia_cli and aesophia_http stuff from change log	2019-11-25 12:07:05 +01:00
Ulf Norell	8984ecc32d	Bump version numbers	2019-11-25 11:55:31 +01:00
Ulf Norell	025c837886	4.1.0-rc1 change log	2019-11-25 11:52:42 +01:00
Ulf Norell	06e6138de1	Merge release notes for 4.0.0 release candidates into 4.0.0 entry	2019-11-25 11:42:05 +01:00
Ulf Norell	7eb4423e70	Merge pull request #180 from aeternity/fate-optimization-fixes Sophia FATE backend overhaul	2019-11-25 11:29:35 +01:00
Ulf Norell	bd64260e37	Remove impossible case h/t dialyzer	2019-11-25 10:42:37 +01:00
Ulf Norell	6380e04a97	Strip switches on variants with only catch-all	2019-11-19 16:39:01 +01:00
Ulf Norell	2be3c9194d	Optimize switches with a single successful branch Typical case: require(_, _)	2019-11-19 15:14:00 +01:00
Ulf Norell	d0cfd9cbbe	Export to_basic_blocks for tests	2019-11-19 13:11:06 +01:00
Ulf Norell	7f7f53e044	Fix issue in basic block generation	2019-11-19 13:10:56 +01:00
Ulf Norell	7d8a773d6a	Fix type specs	2019-11-19 13:10:26 +01:00
Ulf Norell	d3f5d7f5c5	Fix lost dependency when inlining switch target	2019-11-18 12:20:32 +01:00
Ulf Norell	0b474843f9	Protect against ill-typed code	2019-11-18 12:20:32 +01:00
Ulf Norell	1a628ab29f	Fix bad annotations on switch-body	2019-11-18 12:20:32 +01:00
Ulf Norell	03ad1ad1dd	Protect switch optimizations against ill-typed code	2019-11-18 12:20:32 +01:00
Ulf Norell	bfcb9ab324	Annotate switch bodies	2019-11-18 12:20:32 +01:00
Ulf Norell	4cc88be296	Desugar `STORE R a` to `POP R`	2019-11-18 12:20:32 +01:00
Ulf Norell	505603ad71	More optimizations for impure instructions	2019-11-18 12:20:32 +01:00
Ulf Norell	2d7c860e3a	Rewrite liveness analysis	2019-11-18 12:20:32 +01:00
Ulf Norell	4976e0402e	Don't crash constant propagation on ill-typed code	2019-11-18 12:20:32 +01:00
Ulf Norell	0478df72fc	Fix dependency analysis for loops	2019-11-18 12:20:32 +01:00
Ulf Norell	35b20800c9	Refactor argument inlining optimization	2019-11-18 12:20:32 +01:00
Ulf Norell	d4c5c610ee	Don't include stack and immediates in liveness annotations	2019-11-18 12:20:32 +01:00
Ulf Norell	6868bec3ed	Fix bug in dependency analysis of GAS	2019-11-18 12:20:32 +01:00
Ulf Norell	e5702c068c	Impure == writes to the chain Reading is ok	2019-11-18 12:20:31 +01:00
Ulf Norell	a4b21063e3	Get rid of IsOp	2019-11-18 12:20:31 +01:00
Ulf Norell	aca6b89fcf	Store arguments are now separate from vars	2019-11-18 12:20:31 +01:00
Ulf Norell	13b196568b	Handle reads from undefined variables in liveness analysis Doesn't affect well-formed code, but makes testing easier.	2019-11-18 12:20:31 +01:00
Ulf Norell	eba4f1c79c	Call instructions read the function argument	2019-11-18 12:20:31 +01:00
Ulf Norell	1ca3018958	Don't run pretty printer if not pretty printing	2019-11-18 12:20:31 +01:00
Ulf Norell	e6b5c5a526	Fix bug in short-cut for IS_NIL	2019-11-18 12:20:31 +01:00
Ulf Norell	47ad607dd5	Handle arbitrary store registers	2019-11-18 12:20:31 +01:00
Ulf Norell	e8a54395bf	Export optimize_fun for tests	2019-11-18 12:20:31 +01:00
Ulf Norell	a87065c3a0	Merge pull request #177 from aeternity/GH-174-encode-decode-bits-lima GH-174 Encode/decode bits. Now also for Lima	2019-11-18 12:19:47 +01:00
Ulf Norell	49f9ef955f	Prefix format annotation for negative numbers	2019-11-18 12:16:04 +01:00
Ulf Norell	f42353b300	Handle encoding/decoding bits Fixes GH-174	2019-11-18 12:16:04 +01:00
Ulf Norell	5d23a76094	Merge pull request #173 from aeternity/GH-172-validate-byte-code Add function to validate byte code against source code	2019-11-18 10:00:04 +01:00
Ulf Norell	878140e03c	Add function to validate byte code against source code	2019-11-15 14:22:44 +01:00
Hans Svensson	ac58eb4259	Merge pull request #171 from aeternity/GH-170-stdlib_in_escript Add stdlib include handling when inside an escript	2019-11-11 11:40:29 +01:00
Hans Svensson	22b88bd393	Add stdlib include handling when inside an escript	2019-11-11 11:05:07 +01:00
Ulf Norell	83c3015899	Merge pull request #169 from aeternity/fix-illformed-lex-errors Fix mangled lex errors	2019-10-21 09:00:43 +02:00
Ulf Norell	ec9434fbfd	Fix mangled lex errors	2019-10-21 08:53:32 +02:00
Hans Svensson	b81312a714	Merge pull request #165 from aeternity/GH-164-prepare_release Prepare release - v4.0.0	2019-10-11 15:52:29 +02:00
Hans Svensson	63c0b714d0	Prepare release - v4.0.0	2019-10-11 15:16:00 +02:00
Ulf Norell	d018cc5819	Merge pull request #168 from aeternity/compiler-bug Fix bug in compiler optimization	2019-10-10 14:35:56 +02:00
Ulf Norell	f5b2732b04	Don't get rid of store updates!	2019-10-10 14:19:56 +02:00
Hans Svensson	f86f7984f4	Merge pull request #167 from aeternity/radrow-patch-1 Fix not instantiated uvar	2019-10-10 08:31:48 +02:00
Radosław Rowicki	1ae0a42071	Fix not instantiated uvar	2019-10-09 17:42:12 +02:00
Ulf Norell	18ae801333	Merge pull request #162 from aeternity/address-to-contract Add Address.to_contract	2019-10-01 14:28:32 +02:00
Ulf Norell	32d52f0abc	Merge pull request #163 from aeternity/fail-on-multiple-contracts Fail on defined functions in contract prototypes	2019-10-01 14:28:06 +02:00
Ulf Norell	5e6ff6c9a7	Nice type error if contract function is called as from a namespace	2019-10-01 14:13:56 +02:00
Ulf Norell	2d6d506d63	Fail on function definitions in contracts other than the main contract	2019-10-01 14:13:54 +02:00
Ulf Norell	482d22d46b	Merge pull request #161 from aeternity/version-pragmas add pragma to check compiler version	2019-10-01 14:10:06 +02:00
Ulf Norell	a333888fb9	aebytecode commit	2019-09-30 14:47:26 +02:00
Ulf Norell	5fc6e18cd2	Add Address.to_contract Casts an address to a (any) contract type.	2019-09-30 14:47:05 +02:00
Ulf Norell	dd94a6bd67	add pragma to check compiler version	2019-09-27 17:31:10 +02:00
Hans Svensson	7f86b7d301	Merge pull request #160 from aeternity/prepare_rc5 Prepare 4.0.0-rc5	2019-09-27 09:34:49 +02:00
Hans Svensson	e018c31ce1	Prepare 4.0.0-rc5	2019-09-27 09:06:52 +02:00
Ulf Norell	9234690d31	Merge pull request #159 from aeternity/more-compiler-fixes Fix issues with liveness analysis	2019-09-27 08:45:37 +02:00
Ulf Norell	214a5f0a91	Fix issues with liveness analysis	2019-09-24 16:23:50 +02:00
Ulf Norell	d4d3a9650a	Merge pull request #158 from aeternity/fix-code-generation-bug Don't confuse variables and store registers in fate asm generation	2019-09-24 14:55:08 +02:00
Ulf Norell	b752965443	don't call aeb_fate_ops with {store, _} arg (to not upset dialyzer)	2019-09-24 10:47:26 +02:00
Ulf Norell	0019d92e45	Don't confuse variables and store registers in fate asm generation	2019-09-23 16:52:16 +02:00
Ulf Norell	29f2168827	Merge pull request #157 from aeternity/big-number-literals Allow underscore separators in number and bytes literals	2019-09-23 14:11:11 +02:00
Ulf Norell	f81dc88526	Allow underscore separators in number and bytes literals For instance, `1_000_000_000` or `#FFFF_FFFF_FFFF_FFFF`	2019-09-23 14:04:09 +02:00
Ulf Norell	a21715a657	Merge pull request #156 from aeternity/fix-compiler-crash-bug Fix bug with missing fields causing compiler crash	2019-09-23 11:56:30 +02:00
Ulf Norell	048c2ca98d	Fix bug with missing fields causing compiler crash ... if under a lambda or switch.	2019-09-23 11:40:15 +02:00
Ulf Norell	662e5e70ef	Merge pull request #153 from aeternity/src-loc-for-fun-app Fix bug with missing source location for function applications	2019-09-14 15:36:02 +02:00
Ulf Norell	8e3483ced4	Merge pull request #154 from aeternity/bug-with-old-tuple-syntax Fix bug when using old tuple syntax	2019-09-14 15:35:37 +02:00
Ulf Norell	6efc390bb6	Fix bug when using old tuple syntax	2019-09-14 14:44:25 +02:00
Ulf Norell	981027b2e7	Test case for function application source location	2019-09-14 12:12:55 +02:00
Ulf Norell	11d998b739	Set source location for function applications	2019-09-14 12:09:02 +02:00
Hans Svensson	b481b3254b	Merge pull request #152 from aeternity/prepare_rc4 Prepare v4.0.0-rc4	2019-09-13 08:12:05 +02:00
Hans Svensson	01a2efb7b8	Prepare v4.0.0-rc4	2019-09-13 08:08:47 +02:00
Hans Svensson	a730fcc366	Merge pull request #151 from aeternity/fix_numeric_escapes Fix numeric escapes in strings	2019-09-13 08:04:06 +02:00
Hans Svensson	457f9cf4ea	Remove comment + CHANGELOG	2019-09-12 21:31:25 +02:00
Hans Svensson	f34b6ed982	Fix numeric escapes	2019-09-12 21:17:01 +02:00