Re: [Haskell-cafe] function result caching

thank you for all the answers i was aware lists are is not the best solution, but i was too keen to see the actual result I'll do some tests though using different variants, because i have the feeling that in my next program I'll face the "strong" form of this problem. On 10/13/06, Silviu Gheorghe wrote:

it does, thank you very much for the quick answer, unfortunately as I understand it, it doesn't work well on ints :(

for just now i created a list

slowFunctionCacheList= [slowFunction (i) | i <-[0..5000000]] and use "slowFunctionCacheList !! i" instead of "slowFunction (i)"

it helped alot (i mean i stoped the program after "3 hours still working" and got the result in 2 minutes :))

i am still curious about a better method (and a general one), because this is ugly, and it only works on ints as i see it.

but then again thank you for telling me it doesn't do it, because i had the false impresion it does and i wouldn't stop it otherwise

On 10/13/06, Tom Phoenix wrote:

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On 10/12/06, Silviu Gheorghe wrote:

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I'd like to know if the results are "cached" by the compiler

Hardly ever, as I understand things.

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if they are not I'd like to know what is the best way to cache them manually, and where can I read more about this, and the optimizations the compiler does, because I've searched the web before and i found very little on this topic.

You need to search for the word "memoize" (or "memoise"). Here's a page about a memo function for GHC.

http://www.haskell.org/ghc/docs/6.4.2/html/hslibs/memo-library.html

Hope this helps!

--Tom Phoenix