[Haskell-cafe] Poor libraries documentation

[Anton van Straaten]

Derek Elkins wrote:
> On Thu, 2008-01-31 at 02:18 +0000, Neil Mitchell wrote:
...
>> It isn't something that would throw a C programmer off, but it is
>> something that could confuse a pure Haskell programmer. And the only
>> way I could be sure of radians versus degrees was by trying it out,
>> not a great strategy for determining the implementation of functions!
> 
> Uh, why not?  Often that's exactly what I do as checking even
> conveniently located documentation is more time consuming than just
> trying it.

I agree, but at the risk of veering uncharacteristically off-topic for 
haskell-cafe, I think it's an interesting example of the degree of 
assurance about correctness we're willing to accept in practice, in real 
development.

We discover a function called, say, "cos", probably by guessing it's 
name, run a very small number of simple tests on it, see the answers we 
expect, and decide that it's the function we want.  Does anyone want to 
defend that on safety/correctness grounds?  But some of us do it anyway.

(I'll have to work this into the upcoming paper I mentioned, "In defense 
of arbitrary untracked effects in high assurance software."  I'm glad 
Graham Fawcett volunteered to co-author!)