- (bytestring-index bytevector pred [start end])procedure
- (bytestring-index-right bytevector pred [start end])procedure
Searches bytevector from start to end / from end to start for the first byte that satisfies pred, and returns the index into bytevector containing that byte. In either direction, start is inclusive and end is exclusive. If there are no such bytes, returns #f.
(bytestring-index #u8(#x65 #x72 #x83 #x6f) (lambda (b) (> b #x7f))) ⇒ 2 (bytestring-index #u8"Beeblebrox" (lambda (b) (> b #x7f))) ⇒ #f (bytestring-index-right #u8"Zaphod" odd?) ⇒ 4