src/aeso_ast_infer_types.erl

@@ -798,7 +798,7 @@ check_sccs(Env = #env{}, Funs, [{acyclic, X} | SCCs], Acc) ->
     end;
 check_sccs(Env = #env{}, Funs, [{cyclic, Xs} | SCCs], Acc) ->
     Defs = [ maps:get(X, Funs) || X <- Xs ],
-    {TypeSigs, {letrec, _, Defs1}} = infer_letrec(Env, {letrec, [], Defs}),
+    {TypeSigs, Defs1} = infer_letrec(Env, Defs),
     Env1 = bind_funs(TypeSigs, Env),
     check_sccs(Env1, Funs, SCCs, Defs1 ++ Acc).
 
@@ -840,7 +840,7 @@ check_special_funs(_, _) -> ok.
 
 typesig_to_fun_t({type_sig, Ann, Named, Args, Res}) -> {fun_t, Ann, Named, Args, Res}.
 
-infer_letrec(Env, {letrec, Attrs, Defs}) ->
+infer_letrec(Env, Defs) ->
     create_constraints(),
     Funs = [{Name, fresh_uvar(A)}
                  || {letfun, _, {id, A, Name}, _, _, _} <- Defs],
@@ -860,7 +860,7 @@ infer_letrec(Env, {letrec, Attrs, Defs}) ->
     TypeSigs = instantiate([Sig || {Sig, _} <- Inferred]),
     NewDefs  = instantiate([D || {_, D} <- Inferred]),
     [print_typesig(S) || S <- TypeSigs],
-    {TypeSigs, {letrec, Attrs, NewDefs}}.
+    {TypeSigs, NewDefs}.
 
 infer_letfun(Env, {letfun, Attrib, {id, NameAttrib, Name}, Args, What, Body}) ->
     ArgTypes  = [{ArgName, check_type(Env, arg_type(T))} || {arg, _, ArgName, T} <- Args],
@@ -1133,12 +1133,11 @@ infer_case(Env, Attrs, Pattern, ExprType, Branch, SwitchType) ->
 %% NewStmts = infer_block(Env, Attrs, Stmts, BlockType)
 infer_block(_Env, Attrs, [], BlockType) ->
     error({impossible, empty_block, Attrs, BlockType});
-infer_block(Env, Attrs, [Def={letfun, _, _, _, _, _}|Rest], BlockType) ->
-    NewDef = infer_letfun(Env, Def),
-    [NewDef|infer_block(Env, Attrs, Rest, BlockType)];
-infer_block(Env, Attrs, [Def={letrec, _, _}|Rest], BlockType) ->
-    NewDef = infer_letrec(Env, Def),
-    [NewDef|infer_block(Env, Attrs, Rest, BlockType)];
+infer_block(Env, Attrs, [Def={letfun, Ann, _, _, _, _}|Rest], BlockType) ->
+    {{Name, TypeSig}, LetFun} = infer_letfun(Env, Def),
+    FunT = freshen_type(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(Type)}),
     {'case', _, NewPattern, {typed, _, {block, _, NewRest}, _}} =

src/aeso_ast_to_fcode.erl

@@ -722,6 +722,9 @@ decision_tree_to_fcode({'if', A, Then, Else}) ->
 -spec stmts_to_fcode(env(), [aeso_syntax:stmt()]) -> fexpr().
 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, [{letfun, Ann, {id, _, X}, Args, _Type, Expr} | Stmts]) ->
+    {'let', X, expr_to_fcode(Env, {lam, Ann, Args, Expr}),
+               stmts_to_fcode(bind_var(Env, X), Stmts)};
 stmts_to_fcode(Env, [Expr]) ->
     expr_to_fcode(Env, Expr);
 stmts_to_fcode(Env, [Expr | Stmts]) ->

src/aeso_ast_to_icode.erl

@@ -102,13 +102,6 @@ contract_to_icode([{letfun, Attrib, Name, Args, _What, Body={typed,_,_,T}}|Rest]
     QName    = aeso_icode:qualify(Name, Icode),
     NewIcode = ast_fun_to_icode(ast_id(QName), FunAttrs, FunArgs, FunBody, TypeRep, Icode),
     contract_to_icode(Rest, NewIcode);
-contract_to_icode([{letrec,_,Defs}|Rest], Icode) ->
-    %% OBS! This code ignores the letrec structure of the source,
-    %% because the back end treats ALL declarations as recursive! We
-    %% need to decide whether to (a) modify the back end to respect
-    %% the letrec structure, or (b) (preferably) modify the front end
-    %% just to parse a list of (mutually recursive) definitions.
-    contract_to_icode(Defs++Rest, Icode);
 contract_to_icode([], Icode) -> Icode;
 contract_to_icode([{fun_decl, _, _, _} | Code], Icode) ->
     contract_to_icode(Code, Icode);
@@ -530,6 +523,8 @@ ast_body({switch,_,A,Cases}, Icode) ->
 ast_body({block,As,[{letval,_,Pat,_,E}|Rest]}, Icode) ->
     #switch{expr=ast_body(E, Icode),
             cases=[{ast_body(Pat, Icode),ast_body({block,As,Rest}, Icode)}]};
+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);
 ast_body({block,_,[]}, _Icode) ->
     #tuple{cpts=[]};
 ast_body({block,_,[E]}, Icode) ->

src/aeso_fcode_to_fate.erl

@@ -241,7 +241,7 @@ to_scode(Env, {remote, Ct, Fun, [{builtin, call_gas_left, _}, Value | Args]}) ->
     Call = if Env#env.tailpos -> aeb_fate_code:call_tr(?a, Lbl, ?a);
               true            -> aeb_fate_code:call_r(?a, Lbl, ?a)
            end,
-    call_to_scode(Env, [to_scode(Env, Value), to_scode(Env, Ct), Call], Args);
+    call_to_scode(Env, Call, [Ct, Value | Args]);
 
 to_scode(Env, {remote, Ct, Fun, [Gas, Value | Args]}) ->
     %% Gas is limited.
@@ -249,10 +249,7 @@ to_scode(Env, {remote, Ct, Fun, [Gas, Value | Args]}) ->
     Call = if Env#env.tailpos -> aeb_fate_code:call_gtr(?a, Lbl, ?a, ?a);
               true            -> aeb_fate_code:call_gr(?a, Lbl, ?a, ?a)
            end,
-    call_to_scode(Env, [to_scode(Env, Gas),
-                        to_scode(Env, Value),
-                        to_scode(Env, Ct), Call],
-                  Args);
+    call_to_scode(Env, Call, [Ct, Value, Gas | Args]);
 
 to_scode(Env, {closure, Fun, FVs}) ->
     to_scode(Env, {tuple, [{lit, {string, make_function_name(Fun)}}, FVs]});

src/aeso_parser.erl

@@ -87,7 +87,7 @@ constructors() ->
     sep1(constructor(), tok('|')).
 
 constructor() ->    %% TODO: format for Con() vs Con
-    choice(?RULE(con(),              {constr_t, get_ann(_1), _1, []}),
+    choice(?RULE(con(),             {constr_t, get_ann(_1), _1, []}),
            ?RULE(con(), con_args(), {constr_t, get_ann(_1), _1, _2})).
 
 con_args()   -> paren_list(con_arg()).
@@ -99,9 +99,7 @@ con_arg()    -> choice(type(), ?RULE(keyword(indexed), type(), set_ann(indexed,
 %% -- Let declarations -------------------------------------------------------
 
 letdecl() ->
-    choice(
-        ?RULE(keyword('let'), letdef(),                             set_pos(get_pos(_1), _2)),
-        ?RULE(keyword('let'), tok(rec), sep1(letdef(), tok('and')), {letrec, _1, _3})).
+    ?RULE(keyword('let'), letdef(), set_pos(get_pos(_1), _2)).
 
 letdef() -> choice(valdef(), fundef()).
 

src/aeso_pretty.erl

@@ -160,8 +160,7 @@ decl(D = {letfun, Attrs, _, _, _, _}) ->
                             text(atom_to_list(Mod));
              (_) -> empty() end,
     hsep(lists:map(Mod, Attrs) ++ [letdecl("function", D)]);
-decl(D = {letval, _, _, _, _})    -> letdecl("let", D);
-decl(D = {letrec, _, _})          -> letdecl("let", D).
+decl(D = {letval, _, _, _, _}) -> letdecl("let", D).
 
 -spec expr(aeso_syntax:expr(), options()) -> doc().
 expr(E, Options) ->
@@ -184,9 +183,7 @@ name({typed, _, Name, _}) -> name(Name).
 letdecl(Let, {letval, _, F, T, E}) ->
     block_expr(0, hsep([text(Let), typed(name(F), T), text("=")]), E);
 letdecl(Let, {letfun, _, F, Args, T, E}) ->
-    block_expr(0, hsep([text(Let), typed(beside(name(F), args(Args)), T), text("=")]), E);
-letdecl(Let, {letrec, _, [D | Ds]}) ->
-    hsep(text(Let), above([ letdecl("rec", D) | [ letdecl("and", D1) || D1 <- Ds ] ])).
+    block_expr(0, hsep([text(Let), typed(beside(name(F), args(Args)), T), text("=")]), E).
 
 -spec args([aeso_syntax:arg()]) -> doc().
 args(Args) ->
@@ -435,7 +432,6 @@ statements(Stmts) ->
 
 statement(S = {letval, _, _, _, _})    -> letdecl("let", S);
 statement(S = {letfun, _, _, _, _, _}) -> letdecl("let", S);
-statement(S = {letrec, _, _})          -> letdecl("let", S);
 statement(E) -> expr(E).
 
 get_elifs(Expr) -> get_elifs(Expr, []).

src/aeso_scan.erl

@@ -36,8 +36,8 @@ lexer() ->
         , {"\\*/",        pop(skip())}
         , {"[^/*]+|[/*]", skip()} ],
 
-    Keywords = ["contract", "include", "let", "rec", "switch", "type", "record", "datatype", "if", "elif", "else", "function",
-                "stateful", "true", "false", "and", "mod", "public", "private", "indexed", "internal", "namespace"],
+    Keywords = ["contract", "include", "let", "switch", "type", "record", "datatype", "if", "elif", "else", "function",
+                "stateful", "true", "false", "mod", "public", "private", "indexed", "internal", "namespace"],
     KW = string:join(Keywords, "|"),
 
     Rules =

src/aeso_syntax.erl

@@ -43,8 +43,7 @@
 
 -type letbind()
     :: {letval, ann(), id(), type(), expr()}
-     | {letfun, ann(), id(), [arg()], type(), expr()}
-     | {letrec, ann(), [letbind()]}.
+     | {letfun, ann(), id(), [arg()], type(), expr()}.
 
 -type arg() :: {arg, ann(), id(), type()}.
 

src/aeso_syntax_utils.erl

@@ -39,11 +39,6 @@ fold(Alg = #alg{zero = Zero, plus = Plus, scoped = Scoped}, Fun, K, X) ->
     BindExpr = fun(P) -> fold(Alg, Fun, bind_expr, P) end,
     BindType = fun(T) -> fold(Alg, Fun, bind_type, T) end,
     Top = Fun(K, X),
-    Bound = fun LB ({letval, _, Y, _, _})    -> BindExpr(Y);
-                LB ({letfun, _, F, _, _, _}) -> BindExpr(F);
-                LB ({letrec, _, Ds})         -> Sum(lists:map(LB, Ds));
-                LB (_)                       -> Zero
-            end,
     Rec = case X of
             %% lists (bound things in head scope over tail)
             [A | As]                 -> Scoped(Same(A), Same(As));
@@ -55,7 +50,6 @@ fold(Alg = #alg{zero = Zero, plus = Plus, scoped = Scoped}, Fun, K, X) ->
             {fun_decl, _, _, T}      -> Type(T);
             {letval, _, F, T, E}     -> Sum([BindExpr(F), Type(T), Expr(E)]);
             {letfun, _, F, Xs, T, E} -> Sum([BindExpr(F), Type(T), Scoped(BindExpr(Xs), Expr(E))]);
-            {letrec, _, Ds}          -> Plus(Bound(Ds), Decl(Ds));
             %% typedef()
             {alias_t, T}    -> Type(T);
             {record_t, Fs}  -> Type(Fs);

test/aeso_compiler_tests.erl

@@ -86,6 +86,7 @@ compilable_contracts() ->
      "dutch_auction",
      "environment",
      "factorial",
+     "functions",
      "fundme",
      "identity",
      "maps",

test/aeso_scan_tests.erl

@@ -41,7 +41,7 @@ all_tokens() ->
     %% Operators
     lists:map(Lit, ['=', '==', '!=', '>', '<', '>=', '=<', '-', '+', '++', '*', '/', mod, ':', '::', '->', '=>', '||', '&&', '!']) ++
     %% Keywords
-    lists:map(Lit, [contract, type, 'let', switch, rec, 'and']) ++
+    lists:map(Lit, [contract, type, 'let', switch]) ++
     %% Comment token (not an actual token), just for tests
     [{comment, 0, "// *Comment!\"\n"},
      {comment, 0, "/* bla /* bla bla */*/"}] ++

test/contracts/all_syntax.aes

@@ -36,11 +36,6 @@ contract AllSyntax =
       (x, [y, z]) => bar({x = z, y = -y + - -z * (-1)})
       (x, y :: _) => ()
 
-  function mutual() =
-    let rec recFun(x : int) = mutFun(x)
-        and mutFun(x) = if(x =< 0) 1 else x * recFun(x - 1)
-    recFun(0)
-
   let hash : address = #01ab0fff11
   let b = false
   let qcon = Mod.Con

test/contracts/functions.aes

@@ -0,0 +1,15 @@
+contract Functions =
+  private function curry(f : ('a, 'b) => 'c) =
+    (x) => (y) => f(x, y)
+  private function map(f : 'a => 'b, xs : list('a)) =
+    switch(xs)
+      [] => []
+      x :: xs => f(x) :: map(f, xs)
+  private function map'() = map
+  private function plus(x, y) = x + y
+  function test1(xs : list(int)) = map(curry(plus)(5), xs)
+  function test2(xs : list(int)) = map'()(((x) => (y) => ((x, y) => x + y)(x, y))(100), xs)
+  function test3(xs : list(int)) =
+    let m(f, xs) = map(f, xs)
+    m((x) => x + 1, xs)
+