http://www.purl.org/tcl/home/man/tcl8.4/TclCmd/regsub.htm
[Feel free to add various examples, demonstrating the use of the various flags, etc.]
One example of using regsub from Brent Welch's BOOK Practical Programming in Tcl and Tk is:
regsub -- {([^\.]*)\.c} file.c {cc -c & -o \1.o} ccCmdThe & is replaced by file.c, and the \1 is replaced by file.
Recently on the Tcler's Wiki chat room, someone had the desire to convert a string like this:
rand ||=> this is some text <=|| rand
to
rand ||=> some other text <=|| rand
set unique1 {\|\|=>}
set unique2 {<=\|\|}
set string {rand ||=> this is some text <=|| rand}
set replacement {some other text}
set new [regsub -- "($unique1) .* ($unique2)" $string "\\1$replacement\\2" string ]
puts $new
puts $stringNote that the regular expression metacharacters in unique1 and unique2 need to be quoted so they are not treated as metacharacters.
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