Split desugaring from the type checker

This commit is contained in:
Gaith Hallak 2023-04-24 16:23:18 +03:00
parent ab69b6c2a7
commit a91470fe3c
2 changed files with 118 additions and 103 deletions

View File

@ -208,6 +208,11 @@ potential_unused_return_value(A) -> aeso_tc_warnings:potential_unused_return_val
used_typedef(A, B) -> aeso_tc_warnings:used_typedef(A, B). used_typedef(A, B) -> aeso_tc_warnings:used_typedef(A, B).
all_warnings() -> aeso_tc_warnings:all_warnings(). all_warnings() -> aeso_tc_warnings:all_warnings().
%% -------
desugar(A) -> aeso_tc_desugar:desugar(A).
desugar_clauses(A, B, C, D) -> aeso_tc_desugar:desugar_clauses(A, B, C, D).
%% -- New functions ---------------------------------------------------------- %% -- New functions ----------------------------------------------------------
@ -1731,27 +1736,6 @@ infer_letfun1(Env0 = #env{ namespace = NS }, {letfun, Attrib, Fun = {id, NameAtt
get_letfun_id({fun_clauses, _, Id, _, _}) -> Id; get_letfun_id({fun_clauses, _, Id, _, _}) -> Id;
get_letfun_id({letfun, _, Id, _, _, _}) -> Id. get_letfun_id({letfun, _, Id, _, _, _}) -> Id.
desugar_clauses(Ann, Fun, {type_sig, _, _, _, ArgTypes, RetType}, Clauses) ->
NeedDesugar =
case Clauses of
[{letfun, _, _, As, _, [{guarded, _, [], _}]}] -> 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, [{guarded, NoAnn, [], {typed, NoAnn,
{switch, NoAnn, Tuple(Args),
[ {'case', AnnC, Tuple(ArgsC), GuardedBodies}
|| {letfun, AnnC, _, ArgsC, _, GuardedBodies} <- Clauses ]}, RetType}}]}
end.
print_typesig({Name, TypeSig}) -> print_typesig({Name, TypeSig}) ->
?PRINT_TYPES("Inferred ~s : ~s\n", [Name, pp(TypeSig)]). ?PRINT_TYPES("Inferred ~s : ~s\n", [Name, pp(TypeSig)]).
@ -3246,85 +3230,3 @@ when_warning(Warn, Do) ->
ok ok
end end
end. end.
%% -- Pre-type checking desugaring -------------------------------------------
%% Desugars nested record/map updates as follows:
%% { x.y = v1, x.z @ z = f(z) } becomes { x @ __x = __x { y = v1, z @ z = f(z) } }
%% { [k1].x = v1, [k2].y = v2 } becomes { [k1] @ __x = __x { x = v1 }, [k2] @ __x = __x { y = v2 } }
%% There's no comparison of k1 and k2 to group the updates if they are equal.
desugar({record, Ann, Rec, Updates}) ->
{record, Ann, Rec, desugar_updates(Updates)};
desugar({map, Ann, Map, Updates}) ->
{map, Ann, Map, desugar_updates(Updates)};
desugar([H|T]) ->
[desugar(H) | desugar(T)];
desugar(T) when is_tuple(T) ->
list_to_tuple(desugar(tuple_to_list(T)));
desugar(X) -> X.
desugar_updates([]) -> [];
desugar_updates([Upd | Updates]) ->
{Key, MakeField, Rest} = update_key(Upd),
{More, Updates1} = updates_key(Key, Updates),
%% Check conflicts
case length([ [] || [] <- [Rest | More] ]) of
N when N > 1 -> type_error({conflicting_updates_for_field, Upd, Key});
_ -> ok
end,
[MakeField(lists:append([Rest | More])) | desugar_updates(Updates1)].
%% TODO: refactor representation to make this not horrible
update_key(Fld = {field, _, [Elim], _}) ->
{elim_key(Elim), fun(_) -> Fld end, []};
update_key(Fld = {field, _, [Elim], _, _}) ->
{elim_key(Elim), fun(_) -> Fld end, []};
update_key({field, Ann, [P = {proj, _, {id, _, Name}} | Rest], Value}) ->
{Name, fun(Flds) -> {field, Ann, [P], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [P = {proj, _, {id, _, Name}} | Rest], Id, Value}) ->
{Name, fun(Flds) -> {field, Ann, [P], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]};
update_key({field, Ann, [K = {map_get, _, _} | Rest], Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [K = {map_get, _, _, _} | Rest], Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [K = {map_get, _, _, _} | Rest], Id, Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]};
update_key({field, Ann, [K = {map_get, _, _} | Rest], Id, Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]}.
map_or_record(Ann, Val, Flds = [Fld | _]) ->
Kind = case element(3, Fld) of
[{proj, _, _} | _] -> record;
[{map_get, _, _} | _] -> map;
[{map_get, _, _, _} | _] -> map
end,
{Kind, Ann, Val, Flds}.
elim_key({proj, _, {id, _, Name}}) -> Name;
elim_key({map_get, _, _, _}) -> map_key; %% no grouping on map keys (yet)
elim_key({map_get, _, _}) -> map_key.
updates_key(map_key, Updates) -> {[], Updates};
updates_key(Name, Updates) ->
Xs = [ {Upd, Name1 == Name, Rest}
|| Upd <- Updates,
{Name1, _, Rest} <- [update_key(Upd)] ],
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).

113
src/aeso_tc_desugar.erl Normal file
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@ -0,0 +1,113 @@
-module(aeso_tc_desugar).
-export([ desugar/1
, desugar_clauses/4
]).
%% -- Moved functions --------------------------------------------------------
type_error(A) -> aeso_tc_errors:type_error(A).
%% ---------------------------------------------------------------------------
desugar_clauses(Ann, Fun, {type_sig, _, _, _, ArgTypes, RetType}, Clauses) ->
NeedDesugar =
case Clauses of
[{letfun, _, _, As, _, [{guarded, _, [], _}]}] -> 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, [{guarded, NoAnn, [], {typed, NoAnn,
{switch, NoAnn, Tuple(Args),
[ {'case', AnnC, Tuple(ArgsC), GuardedBodies}
|| {letfun, AnnC, _, ArgsC, _, GuardedBodies} <- Clauses ]}, RetType}}]}
end.
%% -- Pre-type checking desugaring -------------------------------------------
%% Desugars nested record/map updates as follows:
%% { x.y = v1, x.z @ z = f(z) } becomes { x @ __x = __x { y = v1, z @ z = f(z) } }
%% { [k1].x = v1, [k2].y = v2 } becomes { [k1] @ __x = __x { x = v1 }, [k2] @ __x = __x { y = v2 } }
%% There's no comparison of k1 and k2 to group the updates if they are equal.
desugar({record, Ann, Rec, Updates}) ->
{record, Ann, Rec, desugar_updates(Updates)};
desugar({map, Ann, Map, Updates}) ->
{map, Ann, Map, desugar_updates(Updates)};
desugar([H|T]) ->
[desugar(H) | desugar(T)];
desugar(T) when is_tuple(T) ->
list_to_tuple(desugar(tuple_to_list(T)));
desugar(X) -> X.
desugar_updates([]) -> [];
desugar_updates([Upd | Updates]) ->
{Key, MakeField, Rest} = update_key(Upd),
{More, Updates1} = updates_key(Key, Updates),
%% Check conflicts
case length([ [] || [] <- [Rest | More] ]) of
N when N > 1 -> type_error({conflicting_updates_for_field, Upd, Key});
_ -> ok
end,
[MakeField(lists:append([Rest | More])) | desugar_updates(Updates1)].
%% TODO: refactor representation to make this not horrible
update_key(Fld = {field, _, [Elim], _}) ->
{elim_key(Elim), fun(_) -> Fld end, []};
update_key(Fld = {field, _, [Elim], _, _}) ->
{elim_key(Elim), fun(_) -> Fld end, []};
update_key({field, Ann, [P = {proj, _, {id, _, Name}} | Rest], Value}) ->
{Name, fun(Flds) -> {field, Ann, [P], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [P = {proj, _, {id, _, Name}} | Rest], Id, Value}) ->
{Name, fun(Flds) -> {field, Ann, [P], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]};
update_key({field, Ann, [K = {map_get, _, _} | Rest], Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [K = {map_get, _, _, _} | Rest], Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Value}]};
update_key({field, Ann, [K = {map_get, _, _, _} | Rest], Id, Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]};
update_key({field, Ann, [K = {map_get, _, _} | Rest], Id, Value}) ->
{map_key, fun(Flds) -> {field, Ann, [K], {id, [], "__x"},
desugar(map_or_record(Ann, {id, [], "__x"}, Flds))}
end, [{field, Ann, Rest, Id, Value}]}.
map_or_record(Ann, Val, Flds = [Fld | _]) ->
Kind = case element(3, Fld) of
[{proj, _, _} | _] -> record;
[{map_get, _, _} | _] -> map;
[{map_get, _, _, _} | _] -> map
end,
{Kind, Ann, Val, Flds}.
elim_key({proj, _, {id, _, Name}}) -> Name;
elim_key({map_get, _, _, _}) -> map_key; %% no grouping on map keys (yet)
elim_key({map_get, _, _}) -> map_key.
updates_key(map_key, Updates) -> {[], Updates};
updates_key(Name, Updates) ->
Xs = [ {Upd, Name1 == Name, Rest}
|| Upd <- Updates,
{Name1, _, Rest} <- [update_key(Upd)] ],
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).