[Haskell-beginners] hunit question

Joe Van Dyk joe at fixieconsulting.com
Tue Feb 2 16:46:20 EST 2010

On Tue, Feb 2, 2010 at 1:34 PM, Daniel Fischer <daniel.is.fischer at web.de> wrote:
> Am Dienstag 02 Februar 2010 22:18:50 schrieb Joe Van Dyk:
>> I have a little binary search function and am trying to write tests
>> for it in hunit.
>> The below approach doesn't compile, because I'm attempting to build a
>> list of tuples of different types, which isn't working for me.
>> What's the appropriate way to do this test?
> QuickCheck, I'd say. Let that create more testcases than you could bother
> to write out.
> Anyway, for testing lists of different types, you'd need separate tests
> (properties/assertions).
> *But* you don't need that. Because the algorithm is general (works the same
> way for all types in Ord), the only way it could be correct on one type but
> not on another is if the Ord instance of one (or both) of the types is
> incorrect.
> So it's sufficient to test on [Int].

Good point, but I like to prove that to myself.  :D

Any chance anyone can show me how to write a QuickCheck test for this?


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