isSpace is too slow

Donald Bruce Stewart dons at
Sun May 20 08:26:55 EDT 2007

> Hi,
> I'm running a particular benchmark which calls isSpace a lot
> (basically wc -w). There are three ways to do the underlying space
> comparison - using the Haskell Data.Char.isSpace, using the C isspace,
> or using the C iswspace:
> isspace: 0.375
> iswspace: 0.400
> Char.isSpace: 0.672
> Any chance someone could speed this up?  Perhaps just replacing
> isSpace with a direct call to iswspace?

Want to try also the 
    Data.ByteString.Base.isSpaceWord8 :: Word8 -> Bool

We added that originally I think because isSpace was too slow.

-- Don

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