Fergus Henderson
| Hat/Foo/List.hs:1: | Ambiguous occurrence `List' | It could refer to either `Hat.Hat.List', imported from Hat.Prelude at | Hat/Foo/List.hs:30 | or `Hat.Foo.List.List', defined at | Hat/Foo/List.hs:32
Unfortunately, ghc-6 seems to be rather over-eager to report ambiguous use of identifiers, where in fact the usage is not ambiguous (the Hat.Hat versions are only visible qualified, whereas your Foo.List is visible unqualified). In this regard, Hat does steal a couple of identifiers from the user when you are using ghc-6. 'List' is one of these. 'Fun' is another. Ideally we will try to find a fix for this. In the meantime, you can work around the bug either by renaming your own versions of the overlapping identifiers, or always using them qualified (including in export lists). Regards, Malcolm