On Thursday 04 December 2008 00:11:13 Ian Lynagh wrote:
If you have downloaded the source tarball then the preprocessed files
are included. Cabal may be getting confused by the .x files also being
present, so
rm src/Scan.x
should fix it. You may also need to
rm src/Parser.y
if you
On Thursday 04 December 2008 14:24:32 Philip K.F. Hölzenspies wrote:
[16 of 16] Compiling Main ( src/Main.hs,
dist/build/alex/alex-tmp/Main.o )
src/Main.hs:316:25:
Ambiguous type variable `e' in the constraint:
`GHC.Exception.Exception e'
arising from a use of
Hello all,
Please consider the following code:
{-# OPTIONS -Wall #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances#-}
{-# LANGUAGE TypeOperators#-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE OverlappingInstances #-}
{-# LANGUAGE
Turning on UndecidableInstances is the same as saying: OK typechcker,
you can loop if I make a mistake.
I've not looked closely at your code, but if you turn on that flag,
looping is probably not a bug.
-- Lennart
2008/12/4 José Pedro Magalhães [EMAIL PROTECTED]:
Hello all,
Please consider
Hello Lennart,
Yes, but according to the manual (
http://www.haskell.org/ghc/docs/latest/html/users_guide/type-class-extensions.html#undecidable-instances),
Termination is ensured by having a fixed-depth recursion stack. So I would
expect at least termination, which I'm not getting (but I guess
-- Uncommenting the line below causes the typechecker to loop (GHC 6.10.1,
Windows)
--test = f Zero
Is this expected behavior or a bug?
The call f Zero requires a co-inductive proof of the type class
constraint (F Nat):
F Nat = Vieweable Nat /\ F' (View Nat)
= True /\
Hello,
Since hsc2hs is distributed with GHC, I thought this might be a decent
place to ask. I tried to run hsc2hs on a file that I know worked with
my 6.8.3 installation, but now I'm getting the error
/usr/local/lib/ghc-6.10.1/hsc2hs-0.67/template-hsc.h:4:19: error:
HsFFI.h: No such file or
Ah, just to reply to myself the problem was rather simple: hsc2hs
couldn't find any of the header files in the ghc/include directory.
It was easy enough to fix that, but it was weird that installing ghc
didn't take of that for me. Especially since I never had this problem
with previous versions.
