Changes between Version 5 and Version 6 of ClassMethodTypes

Timestamp:

02/01/06 20:02:32 (7 years ago)

Author:

john@…

Comment:

--

ClassMethodTypes

@@ -13 +13 @@
 [http://www.cse.ogi.edu/~mpj/thih/ Typing Haskell in Haskell], and can be turned off in GHC with `-fglasgow-exts`.
 
+== interaction with existentials ==
+
+If this were allowed than existential types of the form
+
+{{{
+data SomeFoo = exists a . Foo a => SomeFoo a
+}}}
+
+
+would have to carry around a dictionary for Num as well as Foo in dictionary passing implementation of type classes.
+
+
+
 == Cons ==