Frank A. Christoph <[EMAIL PROTECTED]>
and Simon L Peyton Jones <[EMAIL PROTECTED]>
wrote
FC> There's no description of the multi-parameter type classes extension
> in the 3.01 user manual; are the extensions implemented as described
> in the link below? (I vaguely recollect Simon posting a message on
> this subject more recently, but I couldn't find it.)
>
> http://www.cs.chalmers.se/~rjmh/Haskell/Messages/Display.cgi?id=171
SPJ> Yes; except that -fallow-overlapping-instances does what it sounds
> like. It will permit overlapping instances provided one completely
> overlaps the other; e.g instance C [a] and instance C [Int].
> ...
What it is all about? I also need the language description for ghc-3.01.
For example, it surprised me with the composed constructs in the
instances. And the overlapping instances, even as presented above, are
of great need. But ghc-3.01 does not understand
-fallow-overlapping-instances at all: `unrecognised option'. ??
------------------
Sergey Mechveliani
[EMAIL PROTECTED]
