Matching structures in signatures

2 files changed, 24 insertions, 1 deletions

diff --git a/src/elaborate.sml b/src/elaborate.sml
index c61a84c1..b232a980 100644
--- a/src/elaborate.sml
+++ b/src/elaborate.sml
@@ -1085,7 +1085,14 @@ fun subSgn env (all1 as (sgn1, _)) (all2 as (sgn2, loc2)) =
                                      end
                                    | _ => NONE)
 
-                      | _ => raise Fail "Not ready for more sig matching"
+                      | L'.SgiStr (x, n2, sgn2) =>
+                        seek (fn sgi1All as (sgi1, _) =>
+                                 case sgi1 of
+                                     L'.SgiStr (x, n1, sgn1) =>
+                                     (subSgn env sgn1 sgn2;
+                                      SOME env)
+                                   | _ => NONE)
+                        (* Add type equations between structures here some day. *)
                 end
         in
             ignore (foldl folder env sgis2)
diff --git a/tests/modules.lac b/tests/modules.lac
index 1bdc685c..5089f17b 100644
--- a/tests/modules.lac
+++ b/tests/modules.lac
@@ -57,3 +57,19 @@ structure Wobble2 = struct
         type s = int
         type t = float
 end
+
+
+structure N = struct
+        type t = string
+        structure N2 = struct
+                type t = int
+                val zero = 0
+        end
+        val x = "Hi"
+end
+signature N = sig
+        structure N2 : NAT
+        type t
+        val x : t
+end
+structure No : N = N