Re: [Haskell-cafe] conflicting variable definitions in pattern

What would you expect foo [id, \x -> x] to be? Martin Hofmann wrote on 15.05.2009 12:09:

It is pretty clear, that the following is not a valid Haskell pattern:

foo (x:x:xs) = x:xs

My questions is _why_ this is not allowed. IMHO, the semantics should be clear: The pattern is expected to succeed, iff 'x' is each time bound to the same term.

Isn't this allowed, because this would require a strict evaluation of the 'x' variables?

Thanks,

Martin

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe