- Fixed inference involving existentials.

1 files changed, 4 insertions, 3 deletions

diff --git a/stdlib/source/lux/math/constructive.lux b/stdlib/source/lux/math/constructive.lux
index 3f12d1a88..5ecd8d0e2 100644
--- a/stdlib/source/lux/math/constructive.lux
+++ b/stdlib/source/lux/math/constructive.lux
@@ -7,6 +7,7 @@
              ["e" error]
              text/format
              (coll [list "list/" Functor<List>]))
+       (lang [type])
        (type abstract)
        [macro]
        (macro [code]
@@ -39,9 +40,9 @@
                 poly.apply
                 (p.after (poly.this Witness))
                 (p.after poly.any)
-                poly.existential)
-      (#e.Success witness-id)
-      (wrap (.list (.` (#.Ex (~ (code.nat witness-id))))))
+                poly.any)
+      (#e.Success identityT)
+      (wrap (.list (type.to-code identityT)))
       
       (#e.Error error)
       (macro.fail error))))