[r6rs-discuss] bitwise-copy-bit-field

Per Bothner per at bothner.com
Wed Jul 16 20:27:29 EDT 2008


R6RS says:

(bitwise-copy-bit-field ei1 ei2 ei3 ei4)    procedure

Ei2 and ei3 must be non-negative, and ei2 must be less than or equal to 
ei3. The bitwise-copy-bit-field procedure returns the result of 
replacing in ei1 the bits at positions from ei2 (inclusive) to ei3 
(exclusive) by the corresponding bits in ei4, which is the fixnum result 
of the following computation:
  ....

(1) I assume "fixnum" is an error.
(2) Rather than "corresponding bits in ei4", which is ambiguous since
it could also mean "the bits in ei4 at positions from ei2 (inclusive)
to ei3 (exclusive)" I suggest "the low-order (- ei3 ei2) bits of ei4".
-- 
	--Per Bothner
per at bothner.com   http://per.bothner.com/



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