[Haskell-cafe] Removing alternate items from a list

[John Lato]

> From: Markus L?ll <markus.l2ll at gmail.com>
>
> So out of curiosity i took the definitions given in this thread, and
> tried to run timing-tests.
> Here's what I ran:
>> ghc -prof -auto-all -o Test Test.h
>> Test +RTS -p
> and then looked in the Test.prof file.

I think this is a poor approach for timing tests, for two reasons:

1) -O or -O2.  Reporting performance results from non-optimized builds
is often highly misleading.
2) -auto-all inhibits performance of code, sometimes significantly.

You'd be better off using a non-profiling build and criterion.  Plus
criterion does the statistics for you and warns about possibly invalid
samples.

John