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  • #2817

Closed
Open
Opened Nov 26, 2008 by Simon Peyton Jones@simonpjDeveloper

Template Haskell conversion fails with "malformed type"

Nicholas Frisby writes: When using Template Taskell (via Derive) to generate this (exact) instance:

  instance Foldable ((->) Int) => Foldable Data.Derivable.InterpreterLib.Test.List
      where foldMap f (Cons x0 x1) = (const mempty Cons `mappend` foldMap f x0)
                                      `mappend` foldMap f x1
            foldMap f (Nil) = const mempty Nil

I realize the context is unsatisfiable. My issue, is that I can't even reach that "challenge". I get this error instead:

   Malformed type AppT ArrowT (ConT GHC.Base.Int)
    When splicing generated code into the program
Trac metadata
Trac field Value
Version 6.10.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC nicolas.frisby@gmail.com
Operating system
Architecture
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6.10.2
Milestone
6.10.2
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Reference: ghc/ghc#2817