Talk:Sieve of Eratosthenes: Difference between revisions
→Recent edits to Haskell and my reversal of them: making functions instead of simple bindings...
GordonBGood (talk | contribs) (→Recent edits to Haskell and my reversal of them: type signatures...) |
GordonBGood (talk | contribs) (→Recent edits to Haskell and my reversal of them: making functions instead of simple bindings...) |
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:::: I do think that you should add type signatures to all of the top level functions for two reasons: 1) its recommended Haskell style, and 2) if there are no signatures, integer numerics default to "Integer" which can be considerably slower than "Int".
:::: I see your point on using the combinator to avoid holding the lists in memory '''for the actual sequence of calculations''', however making each a function as in "primes :: () -> [Int]" rather than "primes :: [Int]" does two things: 1) for noobie people testing timing and such, it means that on every call to the '''function''' the whole calculation sequence starts from the beginning rather than using that portion of the memoized stream already computed, and 2) having the outer binding means that the result stream can not be garbage collected as the stream is consumed by say "head $ drop 1000000 primes" where I am suggesting "head $ drop 1000000 $ primes ()" will not hold onto the results stream and will have a very low memory residency; one does have to be careful when making recursive references (not using "fix" or combinators) as a reference to a function does generate a whole new stream - when that is not desired, internal simple bindings must be used to avoid the generation of new streams when they are not desired. --[[User:GordonBGood|GordonBGood]] ([[User talk:GordonBGood|talk]]) 00:10, 12 April 2015 (UTC)
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