nfjinjing/hack — Issue #1: Fails to build with ghc 7.2.1
Author: pacak
Created: 2011-12-31 12:57:17+00:00
State: open

Configuring hack-2009.10.30...
Preprocessing library hack-2009.10.30...
Building hack-2009.10.30...
[1 of 1] Compiling Hack ( src/Hack.hs, dist/build/Hack.o )

src/Hack.hs:28:10:
Illegal instance declaration for `Show HackErrors'
(All instance types must be of the form (T a1 ... an)
where a1 ... an are *distinct type variables*,
and each type variable appears at most once in the instance head.
Use -XFlexibleInstances if you want to disable this.)
In the instance declaration for `Show HackErrors'