[Haskell-cafe] Re: ANNOUNCE: Utrecht Haskell Compiler (UHC) -- first release

[Richard O'Keefe]

On 21 Apr 2009, at 5:10 pm, Jason Dagit wrote:
> Plus, there was a movement to ban them:

And somehow this means people don't?
> BUT, here is the real point of my reply:
>
> To end this debate as to whether people really use them.  We have this
> huge collection of source code called Hackage.  I bet that if someone
> with haskell-src-ext experience sat down they could go through all of
> package in an automated way and count the number of uses of n+k
> patterns in source code that appears in the wild.

I'm sorry, that wouldn't even come *close* to answering the question.
It's a good way to demonstrate that people *are* using some feature
(like hierarchical package names), but an incredibly bad way to show
that they aren't.  None of the Haskell code I've ever written, for
example, will appear.  Because none of that code was intended for
general use.  If every Haskell user contributed to Hackage, and if
every contributer to Hackage contributed all the code they wrote,
then it would make sense.

In the Erlang mailing list, I frequently use the technique of
trawling through publically available Erlang sources to demonstrate
that features people claim are rare are not.  But I'd never be
silly enough to claim on the basis of such a scan that some feature
_wasn't_ being used extensively in other sources.

If the Haskell Great Powers decide to remove n+k patterns,
so be it.  I can live with that.  It's not my language after all.
I'm profoundly grateful to the people who designed and implemented
it, and who keep stretching my mind with new levels of reuse and
composition.  I won't _like_ the loss of a contributor to readability,
but I can live with it, just as I lived with having to use fmap
instead of map.