allow leaving out fields from record patterns

This commit is contained in:
Ulf Norell 2019-04-11 12:01:37 +02:00
parent bdc5e17ab7
commit 53f88c4c06

View File

@ -103,6 +103,7 @@
, typevars = unrestricted :: unrestricted | [name()]
, fields = #{} :: #{ name() => [field_info()] } %% fields are global
, namespace = [] :: qname()
, in_pattern = false :: boolean()
}).
-type env() :: #env{}.
@ -990,7 +991,7 @@ infer_expr(Env, {record, Attrs, Fields}) ->
constrain([ #record_create_constraint{
record_t = RecordType1,
fields = [ FieldName || {field, _, [{proj, _, FieldName}], _} <- Fields ],
context = Attrs } ] ++
context = Attrs } || not Env#env.in_pattern ] ++
[begin
[{proj, _, FieldName}] = LV,
#field_constraint{
@ -1119,7 +1120,7 @@ infer_case(Env, Attrs, Pattern, ExprType, Branch, SwitchType) ->
[] -> ok;
Nonlinear -> type_error({non_linear_pattern, Pattern, lists:usort(Nonlinear)})
end,
NewEnv = bind_vars([{Var, fresh_uvar(Ann)} || Var = {id, Ann, _} <- Vars], Env),
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),
unify(Env, PatType, ExprType, {case_pat, Pattern, PatType, ExprType}),