pseq strictness properties

Duncan Coutts duncan.coutts at worc.ox.ac.uk
Fri Nov 21 06:20:41 EST 2008


On Fri, 2008-11-21 at 10:53 +0000, Simon Marlow wrote:

> The docs probably shouldn't say anything about what the compiler sees, it 
> should stick to what the programmer sees.  Duncan - do you want to try 
> rewording it?

Hmm, though the difference is really in what transformations you want
the compiler not to do. I would not say the operational behaviour is
actually different. Used in isolation there's really no way to
distinguish them, even using trace and other tricks to observe the
evaluation order.

I guess we can try to simplify it to something like "evaluation happens
here" (pseq) vs "evaluation happens here or before" (seq).

Duncan



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