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Uncaught kind error leads to the 'impossible' happening

data F c a = F (c a)

data Val c a = Val (F c) a --- should produce a kind error but doesn't

t = Val (F [True]) False --- here we get the impossible


dhcp38-137:~/writing/exrep sweirich$ ghci test.hs


/ _ \ /\ /\/ __(_)

/ /\// // / / | | GHC Interactive, version 6.4, for Haskell 98. / /\\/ __ / /| | http://www.haskell.org/ghc/ \__/\/ //\___/|_| Type :? for help.

Loading package base-1.0 ... linking ... done. Compiling Main ( test.hs, interpreted ) ghc-6.4: panic! (the `impossible' happened, GHC version 6.4): Unify.unifyTauTyLists: mismatched type lists!

Please report it as a compiler bug to glasgow-haskell-bugs@haskell.org, or http://sourceforge.net/projects/ghc/.

Trac metadata
Trac field Value
Version 6.4
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture Unknown
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