On Mon, 15 Dec 2008 14:21:51 +0300, Philip Hazel <[email protected]> wrote:
> On Sat, 13 Dec 2008, [email protected] wrote: > >> PCRE Callout documentation says: "You should be aware that, because of >> optimizations in the way PCRE matches patterns, callouts sometimes do >> not happen." >> >> In some cases if user inserts callout, he surely want to deal some >> action at this point. But due to such optimizations (they are >> PCRE-inside and may be unknown for user) expected order may be >> affected. > > It is not the order that is affected. There are shortcuts to failure. > For example, if your pattern is /anything....A/ PCRE knows that there > must be an occurrence of the letter "A" somewhere in the subject string. > Before it even starts matching, it does a quick check. If it does not > find "A", the match fails before it even starts. IMHO, in certain cases it's not quite right. For example, /...(*ACCEPT)...A/ at user's point of view may be accessed without letter "A" occurrence. Are "disordering" optimizations invoked in this case? -- ## List details at http://lists.exim.org/mailman/listinfo/pcre-dev
