[Haskell-cafe] dropSpace not exported in ByteString
dons at galois.com
Thu Nov 15 17:24:00 EST 2007
> Hi all,
> I'm writing a Haskell program to do some address cleansing. The program
> uses the ByteString library.
> Data.ByteString.Char8 documentations shows functions for removing
> whitespace from start or end of a ByteString. Those functions are said to
> be more efficient than the dropWhile / reverse mixes.
> It looks exactly like what I'm searching for, but apparently those
> functions are not exported by the Data.ByteString.Char8 module. Are those
> functions only called by rules? Transformation of dropWhile isSpace into
> dropSpace? I've seen such a rule for dropSpace but did not found an
> equivalent rule for dropSpaceEnd.
> Is there a way to call the dropSpace and dropSpaceEnd or do I have to code
> with dropWhile and hope that some rule will magically transform my
> dropWhileS into dropSpaceS?
"FPS specialise dropWhile isSpace -> dropSpace"
dropWhile isSpace = dropSpace
check that the rule fires with -ddump-simpl-stats
There's no rule for dropSpaceEnd, but you can certainly inline the defn
in your code, if perf. matters.
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