[get type from term rather than variable when eta expanding a definition
John Meacham <john@repetae.net>**20060317215327] hunk ./E/Eta.hs 197
-        (ne,flag) <- f at e (expandPis dataTable $ tvrType t) nameSupply
+        -- note that we can't use the type in the tvr, because it will not have the right free typevars.
+        (ne,flag) <- f at e (expandPis dataTable $ infertype dataTable e) nameSupply