[R6RS] Arithmetic nitpicks
Michael Sperber
sperber at informatik.uni-tuebingen.de
Sun Jul 9 05:17:55 EDT 2006
Two minor points, mainly for Will:
- Given the naming of procedures like `exact-length', shouldn't
`exact-integer-sqrt' be called `exact-sqrt'?
- `exact-length' differs from Common Lisp's `integer-length' on
negative arguments. Is this intentional?
The semantics of both don't make much sense to me: Common Lisp has
(integer-length -8) => 3 for no good reason I can see, even though
the two's complement representation of -8 requires 4 bits. We have
(exact-length -8) => 4, but also (exact-length -9) => 4, even though
the two's complement representation of -9 requires 5 bits. (At
least CL's notion increments at the right point.) Shouldn't we
have:
(exact-length i) => (exact-length (exact-not i)) for i < 0
rather than
(exact-length i) => (exact-length (exact- i)) for i < 0
?
--
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla
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