Boost C++ Libraries: Ticket #3459: Xpressive - Redundant search pattern causes fatal crash

status changed; resolution set

Eric Niebler — Thu, 17 Sep 2009 04:04:18 GMT

status new → closed
resolution → invalid

"[:digit:]" is an invalid regular expression. The code is not crashing. It is throwing an exception, as it should. You probably meant: ":digit:".

cc set

master.universe@… — Thu, 17 Sep 2009 10:01:32 GMT

cc master.universe@… added

Well. But why does [:digit:] throw but [:digi:t] does _not_? No. I really ment [:digit:] . For my favour to be interpreted as possbile match pattern - right?

Eric Niebler — Thu, 17 Sep 2009 16:05:41 GMT

A pattern may contain a character set (which begins with '[' and ends with ']'). A character set may contain a nested posix character set (which begins with "[:" and ends with ":]"). Xpressive's regex parser sees the leading '[' and parses the rest as a character set containing the characters ':', 'd', 'i', 'g', 'i', and 't' (very much not what you want, but perfectly correct according to the ECMA-262 specification). Now it reads ":]" as a single token and, having found a closing posix charset bracket without an opening one, it throws an exception.

I repeat: you meant ":digit:". If you still disagree, please back up your argument with the relevant portion of ECMA-262.