diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/type_check.ml | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/src/type_check.ml b/src/type_check.ml index c32529e4..716e6df5 100644 --- a/src/type_check.ml +++ b/src/type_check.ml @@ -2951,9 +2951,19 @@ and bind_assignment env (LEXP_aux (lexp_aux, _) as lexp) (E_aux (_, (l, ())) as | _ -> assert false end | _ -> - let inferred_exp = irule infer_exp env exp in - let tlexp, env' = bind_lexp env lexp (typ_of inferred_exp) in - annot_assign tlexp inferred_exp, env' + (* Here we have two options, we can infer the type from the + expression, or we can infer the type from the + l-expression. Both are useful in different cases, so try + both. *) + try + let inferred_exp = irule infer_exp env exp in + let tlexp, env' = bind_lexp env lexp (typ_of inferred_exp) in + annot_assign tlexp inferred_exp, env' + with + | Type_error (_, _) -> + let inferred_lexp = infer_lexp env lexp in + let checked_exp = crule check_exp env exp (lexp_typ_of inferred_lexp) in + annot_assign inferred_lexp checked_exp, env and bind_lexp env (LEXP_aux (lexp_aux, (l, ())) as lexp) typ = typ_print (lazy ("Binding mutable " ^ string_of_lexp lexp ^ " to " ^ string_of_typ typ)); |