Re: [Haskell-cafe] Re: General function to count list elements?

A solution with enums would severely suffer from the expression problem... One would need to extent the enums every time one needs to support a new function. Maybe could be solved with type classes, don't know. On Mon, Apr 20, 2009 at 3:57 PM, Achim Schneider wrote:

Lennart Augustsson wrote:

...

On Sun, Apr 19, 2009 at 10:43 PM, Peter Verswyvelen wrote:

...

For example, suppose you have a predicate a -> Bool, and a list of these predicates [a -> Bool], but you want to remove all functions that are obviously equal in the C way from the list for optimization... Okay big hack, and one could do this already with reallyUnsafePtrEquality# I guess...

And when the need gets big enough you pull out StablePtr and use that. :)

Waaagh! Don't give him ideas, he's going to do it... Make yourself an enum, generate your list, nub it, then transform it to a list of functions. Always do everything with the least information sanely feasible, and a function is more information than a value, even if you can't get at it, anymore.

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