[Haskell-cafe] extending bang proposal Re: strict Haskell dialect

Bulat Ziganshin bulatz at HotPOP.com
Mon Feb 6 14:44:46 EST 2006


Hello Robert,

Monday, February 06, 2006, 8:40:11 PM, you wrote:

>>>> foo :: !Int -> !Int
>> btw, it's just implemented in the GHC HEAD
>>

RD> Actually, I think strict _patterns_ are implemented.  You are talking  
RD> about strict _type annotations_, which is rather different.

yes, i was wrong

RD> There has been some work dealing with folding strictness and totality  
RD> information into types systems; I find the resulting type systems  
RD> pretty ugly, and I think they'd be pretty hard to bolt onto an HM base.

i'm not a professor, just a programmer who needs to optimize some code
:)  so, that can be really hard or impossible to implement. what i
mean: given expression "a*b+c" and know that a/b/c is strict Int
values, GHC can determine that whole expression is strict. how it is
fone? i don't know. but i think that strictness annotation on result
type should say compiler just about this

-- 
Best regards,
 Bulat                            mailto:bulatz at HotPOP.com





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