diff options
| -rw-r--r-- | src/elaborate.sml | 15 | ||||
| -rw-r--r-- | tests/subs_sig.lac | 7 | ||||
| -rw-r--r-- | tests/subs_sig.lig | 5 |
3 files changed, 24 insertions, 3 deletions
diff --git a/src/elaborate.sml b/src/elaborate.sml index d2d468db..b4d13f0c 100644 --- a/src/elaborate.sml +++ b/src/elaborate.sml @@ -1353,9 +1353,18 @@ fun subSgn env sgn1 (sgn2 as (_, loc2)) = case sgi1 of L'.SgiSgn (x', n1, sgn1) => if x = x' then - (subSgn env sgn1 sgn2; - subSgn env sgn2 sgn1; - SOME env) + let + val () = subSgn env sgn1 sgn2 + val () = subSgn env sgn2 sgn1 + + val env = E.pushSgnNamedAs env x n2 sgn2 + val env = if n1 = n2 then + env + else + E.pushSgnNamedAs env x n1 sgn2 + in + SOME env + end else NONE | _ => NONE) diff --git a/tests/subs_sig.lac b/tests/subs_sig.lac new file mode 100644 index 00000000..934f6042 --- /dev/null +++ b/tests/subs_sig.lac @@ -0,0 +1,7 @@ +signature S = sig + type t +end + +structure S : S = struct + type t = int +end diff --git a/tests/subs_sig.lig b/tests/subs_sig.lig new file mode 100644 index 00000000..7a6ab8fc --- /dev/null +++ b/tests/subs_sig.lig @@ -0,0 +1,5 @@ +signature S = sig + type t +end + +structure S : S |