Template Haskell doesn't support n+k patterns

ghci> runQ [d| foo (n+3) = 42 |]

<interactive>:1:6:

Exotic pattern not (yet) handled by Template Haskell n+3

Trac metadata

Trac field	Value
Version	7.8.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Template Haskell
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changed weight to 5

added Tbug TemplateHaskell Trac import labels

n+k patterns are often seen as a misfeature and in fact were removed from Haskell 2010. See http://stackoverflow.com/questions/3748592/what-are-nk-patterns-and-why-are-they-banned-from-haskell-2010 for further discussion. I'm tempted to close as "wontfix" but want a concurring opinion before doing so.

I'm also inclined to mark as WONTFIX as well - GHC defaults to H2010 anyway. But I also won't close just yet - I'd also like a few more voices in here. If nobody else speaks up, then yes, I think this is going to be a WONTFIX.

closed

I agree.

Simon

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedWon'tFix

added Pnormal label