[Haskell-cafe] Re: instance Eq (a -> b)

Ketil Malde ketil at malde.org
Wed Apr 14 04:48:53 EDT 2010

Ashley Yakeley <ashley at semantic.org> writes:

>> Another practical consideration is that checking a function taking a
>> simple Int parameter for equality would mean 2^65 function evaluations.
>> I think function equality would be too much of a black hole to be
>> worth it.

> Oh FFS, _don't do that_.

I won't.

But you are the one proposing this functionality and asking why it
isn't there already.  I thought the obvious fact that it won't work in
practice for many built in or easily constructed types might be one such

Same for Show instances for functions, of course.

(If you'd made clear from the start that when you say "Enum a, Bounded a"
you really mean "Bool", you might have avoided these replies that you
apparently find offensive.)

If I haven't seen further, it is by standing in the footprints of giants

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