my RULES don't fire

Daniel Fischer at
Wed Feb 9 18:14:37 CET 2011

On Wednesday 09 February 2011 16:23:15, Sebastian Fischer wrote:
> Why don't the rules fire,

Because the 'match' is at the wrong type. In main, idGen appears as

idGen_anJ :: ([()] -> [[()]]) -> [[()]] -> [[()]]

at some point (yay for ghc -v4), so it doesn't match g's polymorphic type.

> what can I change such that they do,

Type signatures.

> and what to get rid of the warning for the second rule (which I think
> is the one I should use)?

I'll let that for somebody else.

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