[Haskell-beginners] Windows 7 time function

Chaddaï Fouché chaddai.fouche at gmail.com
Sat Mar 5 09:46:22 CET 2011

On Sat, Mar 5, 2011 at 5:48 AM, Daniel Huckstep
<darkhelmet at darkhelmetlive.com> wrote:
> The `time` program runs another programs and tells you how much time was
> spent running it (wall time, user, and system time).
> This program doesn't exist on Windows, so you can ignore it.

Actually it does exist however it doesn't do the same thing as Unix
"time" : it just allows one to show or modify the system clock.
Of course this has absolutely nothing to do with Haskell and in fact
to measure performance of an Haskell program it is enough to use the
RTS to report those statistics :

C:\Users\RenshawFamily\Documents\Scripts\Haskell>A.exe +RTS -N2 -sstderr

should do the trick (note that you don't need time).

Or a library like criterion for more precise and interesting benchmark
(by the way if you use -N2 don't forget to compile your program with
the --threaded option to use the parallel RTS).


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