Regex in STREAM | DevCentral

Unfortunately, TCL only supports lookaheads in regexes–not lookbehinds (negative or positive). I ran into this issue this week. I ended up having to collect the response content, use a more permissive regex with the regexp command and parse the results to only replace the strings that needed to be replaced. It would have been a lot easier with lookbehinds and a stream rule. Ugh…

 

 

 

www.regular-expressions.info/lookaround.html

 

 

Finally, flavors like JavaScript, Ruby and Tcl do not support lookbehind at all, even though they do support lookahead.

 

 

 

 

Aaron