Lorenzo Bettini wrote:
Eric Niebler wrote:
John Maddock wrote:
Hi
is there any plan to support more than 9 back references in the regex library? You can have as many marked sub-expressions as you want, and refer to them in the match_results structure once you have a match. What you can't do at
Lorenzo Bettini wrote: present is have a true back-reference say \12 in your expression.
You could use xpressive, which handles this case.
OK, thanks, I'll take a look at it... is xpressive compatible with boost::regex expressions?
Boost.Regex and Boost.Xpressive accept the same basic regex syntax. Xpressive doesn't yet support collating elements (eg., [.ae.]) and equivalence classes (eg., [=a=]). I should also say that as a result of your inquiry, I found an off-by-one error in Xpressive's handling of back-references over 9. If you want to access back-ref \12, you'll need 13 captures in your expression. Darn. It might be too late to fix for 1.34, but I'll patch the archive in the Vault. It's already fixed in HEAD. -- Eric Niebler Boost Consulting www.boost-consulting.com