Bitwise arithmetic procedures

This proposal is based mainly on SRFI 33, with some changes and additions from Olin's late revisions to SRFI 33 (which were never consummated) and from SRFI 60. Until a full spec is written, see the final column of the table in BitwiseComparison.

Reasons for name changes

BitwiseCowan retains SRFI 33 names for procedures adopted from SRFI 33, with these exceptions:

• The name bitwise-merge is replaced by bitwise-if, the name used in SRFI 60 and R6RS.

• The name extract-bit-field (bit-field-extract in Olin's revisions) is replaced by bit-field, the name used in SRFI 60 and R6RS.

• The names any-bits-set? and all-bits-set? are replaced by any-bit-set? and every-bit-set?, in accordance with Olin's revisions.

• Because copy-bit-field means different things in SRFI 33 and SRFI 60, I have replaced SRFI 33's names replace-bit-field and copy-bit-field (bit-field-replace and bit-field-copy in Olin's revisions) with bit-field-copy and bit-field-copy-same.

The procedures that do not exist in SRFI 33 have their SRFI 60 names, with these exceptions.

• The procedure booleans->integer is a convenient way to specify a bitwise integer in the absence of datum syntax: it accepts an arbitrary number of boolean arguments and returns a non-negative integer. So I gave it the short name bits, roughly analogous to list, string, and vector.

• The names rotate-bit-field and reverse-bit-field are replaced by bit-field-rotate and bit-field-reverse, in parallel with Olin's revisions.