The new Monad instance does not have the method fail. That has been moved exclusively to MonadFail in ghc-8.8.1.
I tried building pipes with the alpha release of the ghc-8.8.1 and the current version results in the following error:
[2 of 6] Compiling Pipes.Core ( src/Pipes/Core.hs, .stack-work/dist/x86_64-linux/Cabal-2.5.0.0/build/Pipes/Core.o )
[3 of 6] Compiling Pipes ( src/Pipes.hs, .stack-work/dist/x86_64-linux/Cabal-2.5.0.0/build/Pipes.o )
/tmp/stack7255/pipes-4.3.9/src/Pipes.hs:426:5: error:
‘fail’ is not a (visible) method of class ‘Monad’
|
426 | fail _ = mzero
| ^^^^
/tmp/stack7255/pipes-4.3.9/src/Pipes.hs:427:16: error:
The INLINE pragma for ‘fail’ lacks an accompanying binding
(The INLINE pragma must be given where ‘fail’ is declared)
|
427 | {-# INLINE fail #-}
| ^^^^
It should be simple enough to fix with some use of the C pre-processor.
The new
Monad
instance does not have the methodfail
. That has been moved exclusively toMonadFail
inghc-8.8.1
.I tried building
pipes
with the alpha release of theghc-8.8.1
and the current version results in the following error:It should be simple enough to fix with some use of the C pre-processor.