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From: davis@ilog.fr (Harley Davis)
Subject: Re: bit manipulation operators in scheme?
In-Reply-To: blume@dynamic.cs.princeton.edu's message of Sat, 12 Nov 1994 16:45:56 GMT
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	<BLUME.94Nov12114556@dynamic.cs.princeton.edu>
Date: 13 Nov 1994 19:59:34 GMT


In article <BLUME.94Nov12114556@dynamic.cs.princeton.edu> blume@dynamic.cs.princeton.edu (Matthias Blume) writes:

      I noticed that the FAQ and the R4RS don't mention bit manipulation
      operators at all. Are there common extensions to do this, or do people
      just not do that in scheme?

   Can someone quickly remind me why one would need bit-operations in Scheme?
   I hardly ever use them in C!

Bitvectors are an efficient way to represent certain sets.  This is
important for large programs on real machines.  I suppose a set of
bitvector operations would be just as good if they could be compiled
efficiently.  Also, bit operations are useful for systems hacking to
avoid costly translations from weird C data reps to more Schemish
ones.  This second reason isn't a good justification for including bit
ops in the language, but the first strikes me as sufficient.

-- Harley Davis
-- 

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