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Integers as Bits [was Re: integer-length]



 | From: Bradley Lucier <lucier@xxxxxxxxxxxxxxx>
 | Date: Fri, 7 Oct 2005 12:47:01 +0200
 | 
 | Jens Axel Søgaard writes:
 | 
 | > I propose adding the following two operations on integers.
 | >
 | >
 | > The first is INTEGER-LENGTH from CLHS
 | >
 | >     <http://clhs.lisp.se/Body/f_intege.htm>
 | >
 | > which returns the number of bits needed to represent a given
 | > integer in binary two's-complement format. Although it is
 | > possible to define INTEGER-LENGTH as a library function, it will
 | > be more efficient as a primitive, since it can exploit the
 | > internal representation of an integer.
 | 
 | Agree completely.

That would bring to 6 the number of procedures (of 19) imported from
SRFI-60 (and SRFI-33).  Shall we continue piecemeal; or should the
incorporation of SRFI-60 procedures be considered in a more organized
fashion?

* bitwise-and
* bitwise-ior
* bitwise-xor
* bitwise-not
  bitwise-merge
  any-bits-set?
  bit-count
* integer-length
  first-set-bit
  bit-set?
  copy-bit
  bit-field
  copy-bit-field
* arithmetic-shift
  rotate-bit-field
  reverse-bit-field
  integer->list
  list->integer
  booleans->integer