This page is part of the web mail archives of SRFI 115 from before July 7th, 2015. The new archives for SRFI 115 contain all messages, not just those from before July 7th, 2015.
There are three optional positional parameters which isa little on the unwieldy side:(regexp-replace re str subst [start end count])but for ease of use I'm allowing #f for the end (0 is shortenough for the start).