type error trying to specialize polymorphic function

The attached module won't compile---definition of 'wrap' is rejected. The error message is

[ 1 of 13] Compiling Pain             ( Pain.hs, Pain.o )

Pain.hs:18:7:
    Couldn't match expected type `n C O' against inferred type `C'
      Expected type: ExTriple (Counter n)
      Inferred type: ExTriple (->)
    In the expression: scalar
    In the definition of `wrap': wrap = scalar

The inferred type is alarming, and in any case the type of wrap is a straightforward specialization of the type of scalar.

Could the problem be with liberal type synonyms? I don't think we're doing anything unreasonable...

Trac metadata

Trac field	Value
Version	6.12.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	dias@cs.tufts.edu
Operating system
Architecture