chickadee » srfi-151 » bitwise-for-each

Repeatedly applies proc to the bits of i starting with bit #0 (inclusive) and ending with bit (integer-length i) (exclusive). The values returned by proc are discarded. Returns an unspecified value.

      (let ((count 0))
        (bitwise-for-each (lambda (b) (if b (set! count (+ count 1))))
                          #b1010111)
       count)