divRem by `-' performance
roma at ro-che.info
Wed Oct 17 18:00:38 CEST 2012
* Serge D. Mechveliani <mechvel at botik.ru> [2012-10-17 19:37:38+0400]
> But it is generally difficult for me to admit that sometimes it is
> desirable to use strinctess annotation.
> I programmed DoCon for 6 years, and it does not have any bit of
> strictness annotation, and I always had an impression that it is all
> right with performance.
Yeah, I was also surprised that this is news to you :)
> And now it occurs that setting $! in some places may make many parts
> of it somewhat 100 times less expensive
> -- ?
> Somehow difficult to admit.
Laziness is subtle. Sometimes you make an innocent change to a program,
but it changes the time when things are evaluated, and that affects
In general, you'd rather understand evaluation order in your program if
you want decent performance.
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