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Branches Tags
QPQ-AG:master
QPQ-AG:uw-ac-side-tx-types
QPQ-AG:uw-account_seckey
QPQ-AG:uw-hash-api-type
QPQ-AG:uw-gmser_dyn-rewrite
QPQ-AG:uw-save-options
QPQ-AG:uw-dyn-options
QPQ-AG:uw-anyint
QPQ-AG:uw-dynamic-encoding2
QPQ-AG:uw-dynamic-encoding
QPQ-AG:eureka
QPQ-AG:runner
QPQ-AG:uw-ac-proposals
QPQ-AG:add_token_swap
QPQ-AG:add_ga_meta_tx_auth_data_type
QPQ-AG:use-latest-enacl-api
QPQ-AG:factories
QPQ-AG:add-subname-id
QPQ-AG:v1.2.0
QPQ-AG:v1.1.0
QPQ-AG:v1.0.0
..
compare: QPQ-AG:uw-anyint
Branches Tags
QPQ-AG:uw-ac-side-tx-types
QPQ-AG:master
QPQ-AG:uw-account_seckey
QPQ-AG:uw-hash-api-type
QPQ-AG:uw-gmser_dyn-rewrite
QPQ-AG:uw-save-options
QPQ-AG:uw-dyn-options
QPQ-AG:uw-anyint
QPQ-AG:uw-dynamic-encoding2
QPQ-AG:uw-dynamic-encoding
QPQ-AG:eureka
QPQ-AG:runner
QPQ-AG:uw-ac-proposals
QPQ-AG:add_token_swap
QPQ-AG:add_ga_meta_tx_auth_data_type
QPQ-AG:use-latest-enacl-api
QPQ-AG:factories
QPQ-AG:add-subname-id
QPQ-AG:v1.2.0
QPQ-AG:v1.1.0
QPQ-AG:v1.0.0

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155
README.md
View File

@ -49,25 +49,8 @@ range from 10 to 200, and also to stay within 1 byte.)
When encoding `map` types, the map elements are first sorted.
When specifying a map type for template-driven encoding, use
the `#{items => [{Key, ValueType} | {opt, Key, ValueType}]}` construct.
The key names are included in the encoding, and are match against the item
specs during decoding. If the key names don't match, the decoding fails, unless
for an `{opt, K, V}` item, in which case that item spec is skipped.
the `#{items => [{Key, Value}]}` construct.
```erlang
T = #{items => [{a,int},{opt,b,int},{c,int}]}
E1 = gmser_dyn:encode_typed(T, #{a => 1, b => 2, c => 3}) ->
[<<0>>,<<1>>,[<<252>>,
[[[<<255>>,<<97>>],[<<248>>,<<1>>]],
[[<<255>>,<<98>>],[<<248>>,<<2>>]],
[[<<255>>,<<99>>],[<<248>>,<<3>>]]]]]
E2 = gmser_dyn:encode_typed(T, #{a => 1, c => 3}) ->
[<<0>>,<<1>>,[<<252>>,
[[[<<255>>,<<97>>],[<<248>>,<<1>>]],
[[<<255>>,<<99>>],[<<248>>,<<3>>]]]]]
gmser_dyn:decode_typed(T,E2) ->
#{c => 3,a => 1}
```
## Labels
@ -75,24 +58,6 @@ Labels correspond to (existing) atoms in Erlang.
Decoding of a label results in a call to `binary_to_existing_atom/2`, so will
fail if the corresponding atom does not already exist.
This behavior can be modified using the option `#{missing_labels => fail | create | convert}`,
where `fail` is the default, as described above, `convert` means that missing atoms are
converted to binaries, and `create` means that the atom is created dynamically.
The option can be passed e.g.:
```erlang
gmser_dyn:deserialize(Binary, gmser_dyn:set_opts(#{missing_labels => convert}))
```
or
```erlang
gmser_dyn:deserialize(Binary, gmser_dyn:set_opts(#{missing_labels => convert}, Types))
```
By calling `gmser_dyn:register_types/1`, after having added options to the type map,
the options can be made to take effect automatically.
It's possible to cache labels for more compact encoding.
Note that when caching labels, the same cache mapping needs to be used on the
decoder side.
@ -131,70 +96,31 @@ Templates can be provided to the encoder by either naming an already registered
type, or by passing a template directly. In both cases, the encoder will enforce
the type information in the template.
If the template has been registered, the encoder uses the registered type specification
to drive the encoding. The code of the registered template is embedded in the encoded
output:
If the template has been registered, the encoder omits inner type tags (still
inserting the top-level tag), leading to some compression of the output.
This also means that the serialized term cannot be decoded without the same
schema information on the decoder side.
In the case of a directly provided template, all type information is inserted,
such that the serialized term can be decoded without any added type information.
The template types are still enforced during encoding.
```erlang
gmser_dyn:encode_typed({int,int,int}, {1,2,3}) ->
[<<0>>,<<1>>,[<<253>>,
[[<<248>>,<<1>>],[<<248>>,<<2>>],[<<248>>,<<3>>]]]]
ET = fun(Type,Term) -> io:fwrite("~w~n", [gmser_dyn:encode_typed(Type,Term)]) end.
Types = gmser_dyn_types:add_type(t3,1013,{int,int,int}).
gmser_dyn:encode_typed(t3, {1,2,3}, Types) ->
[<<0>>,<<1>>,[[<<3,245>>,<<253>>],
[[<<248>>,<<1>>],[<<248>>,<<2>>],[<<248>>,<<3>>]]]]
ET([{int,int}], [{1,2}]) -> [<<0>>,<<1>>,[<<251>>,[[[<<248>>,<<1>>],[<<248>>,<<2>>]]]]]
gmser_dyn:register_type(1000,lt2i,[{int,int}]).
ET(lt2i, [{1,2}]) -> [<<0>>,<<1>>,[<<3,232>>,[[<<1>>,<<2>>]]]]
```
Note that the original `<<253>>` type code is wrapped as `[<<3,245>>,<<253>>]`,
where `<<3,245>>` corresponds to the custom code `1013`.
Using the default option `#{strict => true}`, the decoder will extract the custom
type spec, and validate the encoded data against it. If the custom code is missing,
the decoder aborts. Using `#{strict => false}`, the custom code is used if it exists,
but otherwise, it's ignored, and the encoded data is decoded using the dynamic type
info.
### Alternative types
The dynamic encoder supports a few additions to the `gmserialization` template
language: `any`, `#{list => Type}`, `#{alt => [AltTypes]}` and `#{switch => [AltTypes]}`.
#### `any`
The dynamic encoder supports two additions to the `gmserialization` template
language: `any` and `#{alt => [AltTypes]}`.
The `any` type doesn't have an associated code, but enforces dynamic encoding.
#### `list`
The original list type notation expects a key-value list, e.g.
`[{name, binary}, {age, int}]`
```erlang
EL = gmser_dyn:encode_typed([{name,binary},{age,int}], [{name,<<"Ulf">>},{age,29}]) ->
[<<0>>,<<1>>,[<<251>>,
[[<<253>>,[[<<255>>,<<110,97,109,101>>],[<<249>>,<<85,108,102>>]]],
[<<253>>,[[<<255>>,<<97,103,101>>],[<<248>>,<<29>>]]]]]]
```
Note that the encoding explicitly lays out a `[{Key, Value}]` structure, all
dynamically typed. This means it can be dynamically decoded without templates.
```erlang
gmser_dyn:decode(EL).
[{name,<<"Ulf">>},{age,29}]
```
In order to specify something like Erlang's `[integer()]` type, we can use
the following:
```erlang
gmser_dyn:encode_typed(#{list => int}, [1,2,3,4]) ->
[<<0>>,<<1>>,[<<251>>,
[[<<248>>,<<1>>],[<<248>>,<<2>>],[<<248>>,<<3>>],[<<248>>,<<4>>]]]]
```
#### `alt`
The `#{alt => [Type]}` construct also enforces dynamic encoding, and will try
to encode as each type in the list, in the specified order, until one matches.
@ -206,55 +132,6 @@ gmser_dyn:encode_typed(anyint,-5) -> [<<0>>,<<1>>,[<<246>>,[<<247>>,<<5>>]]]
gmser_dyn:encode_typed(anyint,5) -> [<<0>>,<<1>>,[<<246>>,[<<248>>,<<5>>]]]
```
#### `switch`
The `switch` type allows for encoding a 'tagged' object, where the tag determines
the type.
```erlang
E1 = gmser_dyn:encode_typed(#{switch => #{name => binary, age => int}}, #{age => 29}) ->
[<<0>>,<<1>>,[<<252>>,[[[<<255>>,<<97,103,101>>],[<<248>>,<<29>>]]]]]
gmser_dyn:decode_typed(#{switch => #{name => binary, age => int}}, E1) ->
#{age => 29}
E2 = gmser_dyn:encode_typed(#{switch => #{name => binary, age => int}}, #{name => <<"Ulf">>}) ->
[<<0>>,<<1>>,[<<252>>,[[[<<255>>,<<110,97,109,101>>],[<<249>>,<<85,108,102>>]]]]]
gmser_dyn:decode_typed(#{switch => #{name => binary, age => int}}, E1) ->
#{name => <<"Ulf">>}
```
A practical use of `switch` would be in a protocol schema:
```erlang
t_msg(_) ->
#{switch => #{ call => t_call
, reply => t_reply
, notification => t_notification }}.
t_call(_) ->
#{items => [ {id, anyint}
, {req, t_req} ]}.
t_reply(_) ->
#{alt => [#{items => [ {id, anyint}
, {result, t_result} ]},
#{items => [ {id, anyint}
, {code, anyint}
, {message, binary} ]}
]}.
```
In this scenario, messages are 'taggged' as 1-element maps, e.g.:
```erlang
async_request(Msg) ->
Id = erlang:unique_integer(),
gmmp_cp:to_server(
whereis(gmmp_core_connector),
#{call => #{ id => Id
, req => Msg }}),
Id.
```
### Notes
Note that `anyint` is a standard type. The static serializer supports only

9
rebar.config
View File

@ -7,11 +7,4 @@
{enacl,
{git,
"https://git.qpq.swiss/QPQ-AG/enacl.git",
{ref, "4eb7ec70084ba7c87b1af8797c4c4e90c84f95a2"}}},
{eblake2, "1.0.0"}
]}.
{dialyzer,
[ {plt_apps, all_deps},
{base_plt_apps, [erts, kernel, stdlib, enacl, base58, eblake2]}
]}.
{ref, "4eb7ec70084ba7c87b1af8797c4c4e90c84f95a2"}}}]}.

10
rebar.lock
View File

@ -1,16 +1,8 @@
{"1.2.0",
[{<<"base58">>,
{git,"https://git.qpq.swiss/QPQ-AG/erl-base58.git",
{ref,"e6aa62eeae3d4388311401f06e4b939bf4e94b9c"}},
0},
{<<"eblake2">>,{pkg,<<"eblake2">>,<<"1.0.0">>},0},
{<<"enacl">>,
{git,"https://git.qpq.swiss/QPQ-AG/enacl.git",
{ref,"4eb7ec70084ba7c87b1af8797c4c4e90c84f95a2"}},
0}]}.
[
{pkg_hash,[
{<<"eblake2">>, <<"EC8AD20E438AAB3F2E8D5D118C366A0754219195F8A0F536587440F8F9BCF2EF">>}]},
{pkg_hash_ext,[
{<<"eblake2">>, <<"3C4D300A91845B25D501929A26AC2E6F7157480846FAB2347A4C11AE52E08A99">>}]}
].
0}].

69
src/gmser_api_encoder.erl
View File

@ -13,13 +13,7 @@
safe_decode/2,
byte_size_for_type/1]).
-export([encode_keypair/1,
safe_decode_keypair/1]).
-export([unsafe_encode/2]). %% Encode without size checks
-export_type([encoded/0,
known_type/0]).
-export_type([encoded/0]).
-type known_type() :: key_block_hash
| micro_block_hash
@ -44,7 +38,6 @@
| native_token
| commitment
| peer_pubkey
| hash
| state
| poi
| state_trees
@ -58,66 +51,14 @@
-type payload() :: binary().
-type encoded() :: binary().
-type keypair() :: #{public := <<_:(32*8)>>, secret := <<_:(64*8)>>}.
-type encoded_keypair() :: #{binary() => binary()}.
-export_type([ keypair/0
, encoded_keypair/0 ]).
-define(BASE58, 1).
-define(BASE64, 2).
-spec encode_keypair(keypair()) -> encoded_keypair().
encode_keypair(#{public := Pub, secret := Sec}) ->
case Sec of
<<Seed:32/binary, Pub1:32/binary>> when Pub1 =:= Pub ->
#{ <<"pub">> => encode(account_pubkey, Pub)
, <<"priv">> => encode(account_seckey, Seed) };
_ ->
erlang:error(invalid_keypair)
end.
-spec safe_decode_keypair(encoded_keypair()) -> {'ok', keypair()} | {'error', atom()}.
safe_decode_keypair(#{<<"pub">> := EncPub, <<"priv">> := EncPriv}) ->
case safe_decode(account_pubkey, EncPub) of
{ok, Pub} ->
case safe_decode(account_seckey, EncPriv) of
{ok, Seed} when byte_size(Seed) =:= 32 ->
case enacl:sign_seed_keypair(Seed) of
#{public := Pub, secret := _} = KP ->
{ok, KP};
_ ->
{error, illegal_encoding}
end;
{ok, <<Seed:32/binary, Pub:32/binary>>} ->
case enacl:sign_seed_keypair(Seed) of
#{public := Pub} = KP ->
{ok, KP};
_ ->
{error, illegal_encoding}
end;
{ok, _} ->
{error, illegal_encoding};
{error, _} = Error1 ->
Error1
end;
Error ->
Error
end.
-spec encode(known_type(), payload() | gmser_id:id()) -> encoded().
encode(id_hash, Payload) ->
{IdType, Val} = gmser_id:specialize(Payload),
encode(id2type(IdType), Val);
encode(Type, Payload) ->
case type_size_check(Type, Payload) of
ok ->
unsafe_encode(Type, Payload);
{error, Reason} ->
erlang:error(Reason)
end.
unsafe_encode(Type, Payload) ->
Pfx = type2pfx(Type),
Enc = case type2enc(Type) of
?BASE58 -> base58_check(Payload);
@ -125,7 +66,6 @@ unsafe_encode(Type, Payload) ->
end,
<<Pfx/binary, "_", Enc/binary>>.
-spec decode(binary()) -> {known_type(), payload()}.
decode(Bin0) ->
case split(Bin0) of
@ -141,13 +81,6 @@ decode(Bin0) ->
erlang:error(missing_prefix)
end.
type_size_check(account_seckey, Bin) ->
case byte_size(Bin) of
Sz when Sz =:= 32; Sz =:= 64 ->
ok;
_ ->
{error, incorrect_size}
end;
type_size_check(Type, Bin) ->
case byte_size_for_type(Type) of
not_applicable -> ok;

1070
src/gmser_dyn.erl
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File diff suppressed because it is too large Load Diff

71
src/gmser_dyn_types.erl
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@ -1,71 +0,0 @@
-module(gmser_dyn_types).
-export([ add_type/3 %% (Tag, Code, Template) -> Types1
, add_type/4 %% (Tag, Code, Template, Types) -> Types1
, from_list/2
, expand/1 ]).
-export([ next_code/1 ]).
next_code(#{codes := Codes}) ->
lists:max(maps:keys(Codes)) + 1.
-spec add_type(Tag, Code, Template) -> Types
when Tag :: gmser_dyn:tag()
, Code :: gmser_dyn:code()
, Template :: gmser_dyn:template()
, Types :: gmser_dyn:types().
add_type(Tag, Code, Template) ->
add_type(Tag, Code, Template, gmser_dyn:registered_types()).
add_type(Tag, Code, Template, Types) ->
elem_to_type({Tag, Code, Template}, Types).
from_list(L, Types) ->
lists:foldl(fun elem_to_type/2, Types, L).
expand(#{vsn := V, templates := Templates0} = Types) ->
Templates =
maps:map(
fun(_, F) when is_function(F, 0) ->
F();
(_, F) when is_function(F, 1) ->
F(V);
(_, T) ->
T
end, Templates0),
Types#{templates := Templates}.
elem_to_type({Tag, Code, Template}, Acc) when is_atom(Tag), is_integer(Code) ->
#{codes := Codes, rev := Rev, templates := Temps} = Acc,
case {is_map_key(Tag, Rev), is_map_key(Code, Codes)} of
{false, false} ->
Acc#{ codes := Codes#{Code => Tag}
, rev := Rev#{Tag => Code}
, templates => Temps#{Tag => Template}
};
{true, _} -> error({duplicate_tag, Tag});
{_, true} -> error({duplicate_code, Code})
end;
elem_to_type({modify, {Tag, Template}}, Acc) ->
#{codes := _, rev := Rev, templates := Templates} = Acc,
_ = maps:get(Tag, Rev),
Templates1 = Templates#{Tag := Template},
Acc#{templates := Templates1};
elem_to_type({labels, Lbls}, Acc) ->
lists:foldl(fun add_label/2, Acc, Lbls);
elem_to_type({vsn, V}, Acc) ->
Acc#{vsn => V};
elem_to_type(Elem, _) ->
error({invalid_type, Elem}).
add_label({L, Code}, #{labels := Lbls, rev_labels := RevLbls} = Acc)
when is_atom(L), is_integer(Code), Code > 0 ->
case {is_map_key(L, Lbls), is_map_key(Code, RevLbls)} of
{false, false} ->
Acc#{labels := Lbls#{L => Code},
rev_labels := RevLbls#{Code => L}};
{true, _} -> error({duplicate_label, L});
{_, true} -> error({duplicate_label_code, Code})
end;
add_label(Elem, _) ->
error({invalid_label, Elem}).

21
src/gmser_id.erl
View File

@ -17,9 +17,6 @@
, is_id/1
]).
-export([ t_id/1
]).
%% For aec_serialization
-export([ encode/1
, decode/1
@ -29,18 +26,11 @@
, val
}).
-type tag() :: 'account'
| 'associate_chain'
| 'channel'
| 'commitment'
| 'contract'
| 'contract_source'
| 'name'
| 'native_token'
| 'entry'.
-type tag() :: 'account' | 'name'
| 'commitment' | 'contract' | 'channel'
| 'associate_chain' | 'entry' .
-type val() :: <<_:256>>.
-type id() :: #id{}.
-opaque(id() :: #id{}).
-export_type([ id/0
, tag/0
@ -104,9 +94,6 @@ decode(<<Tag:?TAG_SIZE/unit:8, Val:?PUB_SIZE/binary>>) ->
#id{ tag = decode_tag(Tag)
, val = Val}.
-spec t_id(any()) -> id().
t_id(#id{} = Id) -> Id.
%%%===================================================================
%%% Internal functions
%%%===================================================================

104
test/gmser_api_encoder_tests.erl
View File

@ -22,39 +22,10 @@
, {native_token , 32}
, {commitment , 32}
, {peer_pubkey , 32}
, {hash , 32}
, {state , 32}
, {poi , not_applicable}]).
encode_decode_test_() ->
encode_decode_test_(?TYPES).
encode_decode_known_types_test_() ->
KnownTypes = known_types(),
SizedTypes = [{T, ?TEST_MODULE:byte_size_for_type(T)} || T <- KnownTypes],
encode_decode_test_(SizedTypes).
prefixes_are_known_types_test() ->
MappedPfxs = mapped_prefixes(),
KnownTypes = known_types(),
lists:foreach(
fun({Pfx, Type}) ->
case lists:member(Type, KnownTypes) of
true -> ok;
false ->
error({not_a_known_type, Pfx, Type})
end
end, MappedPfxs),
lists:foreach(
fun(Type) ->
case lists:keyfind(Type, 2, MappedPfxs) of
{_, _} -> ok;
false ->
error({has_no_mapped_prefix, Type})
end
end, KnownTypes).
encode_decode_test_(Types) ->
[{"Byte sizes are correct",
fun() ->
lists:foreach(
@ -62,7 +33,7 @@ encode_decode_test_(Types) ->
{_Type, _, ByteSize} = {Type, ByteSize,
?TEST_MODULE:byte_size_for_type(Type)}
end,
Types)
?TYPES)
end
},
{"Serialize/deserialize known types",
@ -79,7 +50,7 @@ encode_decode_test_(Types) ->
{Type, Key} = ?TEST_MODULE:decode(EncodedKey),
{ok, Key} = ?TEST_MODULE:safe_decode(Type, EncodedKey)
end,
Types)
?TYPES)
end
},
{"Key size check works",
@ -87,18 +58,17 @@ encode_decode_test_(Types) ->
lists:foreach(
fun({_Type, not_applicable}) -> ok;
({Type, ByteSize}) ->
CheckIllegalSize =
CheckIlligalSize =
fun(S) ->
Key = <<42:S/unit:8>>,
?assertError(incorrect_size, ?TEST_MODULE:encode(Type, Key)),
EncodedKey = ?TEST_MODULE:unsafe_encode(Type, Key), %% no size check
EncodedKey = ?TEST_MODULE:encode(Type, Key),
{error, invalid_encoding} = ?TEST_MODULE:safe_decode(Type, EncodedKey)
end,
CheckIllegalSize(0),
CheckIllegalSize(ByteSize - 1),
CheckIllegalSize(ByteSize + 1)
CheckIlligalSize(0),
CheckIlligalSize(ByteSize - 1),
CheckIlligalSize(ByteSize + 1)
end,
Types)
?TYPES)
end
},
{"Missing prefix",
@ -121,7 +91,7 @@ encode_decode_test_(Types) ->
<<_WholePrefix:3/unit:8, RestOfKey2/binary>> = EncodedKey,
{error, invalid_encoding} = ?TEST_MODULE:safe_decode(Type, RestOfKey2)
end,
Types)
?TYPES)
end
},
{"Piece of encoded key",
@ -140,7 +110,7 @@ encode_decode_test_(Types) ->
{error, invalid_encoding} = ?TEST_MODULE:safe_decode(Type, HalfKey),
{error, invalid_encoding} = ?TEST_MODULE:safe_decode(Type, RestOfKey)
end,
Types)
?TYPES)
end
},
{"Encode/decode binary with only zeros",
@ -161,58 +131,8 @@ encode_decode_test_(Types) ->
Encoded1 = base58:binary_to_base58(Bin),
Decoded1 = base58:base58_to_binary(Encoded1),
?assertEqual(Bin, Decoded1)
end, Types)
end, ?TYPES)
end,
Bins)
end},
{"Encode/decode keypairs",
fun() ->
KP1 = enacl:sign_keypair(),
Enc1 = ?TEST_MODULE:encode_keypair(KP1),
{ok, KP1} = ?TEST_MODULE:safe_decode_keypair(Enc1),
KP2 = enacl:sign_keypair(),
Enc2 = ?TEST_MODULE:encode_keypair(KP2),
{ok, KP2} = ?TEST_MODULE:safe_decode_keypair(Enc2),
BadEnc = Enc1#{~"priv" => maps:get(~"priv", Enc2)},
{error, illegal_encoding} = ?TEST_MODULE:safe_decode_keypair(BadEnc)
end
},
{"Encode AND decode both 32-byte and 64-byte account_seckey",
fun() ->
%% Originally, we could encode a 64-byte seckey, but decode would fail.
#{public := Pub, secret := Sec} = enacl:sign_keypair(),
<<Seed:32/binary, Pub:32/binary>> = Sec,
EncSeed = ?TEST_MODULE:encode(account_seckey, Seed),
EncSec = ?TEST_MODULE:encode(account_seckey, Sec),
{ok, Seed} = ?TEST_MODULE:safe_decode(account_seckey, EncSeed),
{ok, Sec} = ?TEST_MODULE:safe_decode(account_seckey, EncSec)
end
}
end}
].
known_types() ->
Forms = get_forms(),
[{type, _, union, Types}] =
[Def || {attribute, _, type, {known_type, Def, []}} <- Forms],
[Name || {atom,_, Name} <- Types].
mapped_prefixes() ->
Forms = get_forms(),
[Clauses] = [Cs || {function,_,pfx2type,1,Cs} <- Forms],
Abst = [{B, A} || {clause,_,[B],[],[A]} <- Clauses],
lists:map(
fun({B, A}) ->
{eval_expr(B), eval_expr(A)}
end, Abst).
get_forms() ->
get_forms(code:which(?TEST_MODULE)).
get_forms(Beam) ->
{ok, {_, [{abstract_code, {raw_abstract_v1, Forms}}]}} =
beam_lib:chunks(Beam, [abstract_code]),
Forms.
eval_expr(Expr) ->
{value, Val, []} = erl_eval:expr(Expr, []),
Val.