Thomas Conway wrote:
Well, maybe I shoud be asking a higher level question then.
I have a function
tidy = reverse . dropWhile punk . reverse . dropWhile punk
where
punk = isPunctuation . chr . fromIntegral
which is leading to a significant amount of allocation, and you can see
why.
The way I'd like to write it is
tidy = dropWhile punk . dropWhileEnd punk
where ....
which has the obvious advantage of avoiding quite a bit of
intermediate allocation.
Is there a another way?
I note that since I'm using a nice declarative language, the compiler
CLEARLY should be transforming the first form into the second. :-)
The NDP library will implement this kind of fusion at some point
(hopefully this year). We have a fairly clear idea of how to do it but
not enough time.
Roman
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