[Boost-users] [xpressive&regex&spirit] Can previous regex be cached?

From: Lynn Allan (l_d_allan_at_[hidden])
Date: 2006-04-11 12:39:42

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Xpressive provides a "tips n tricks" to:
Compiling a regex (dynamic or static) is more expensive than executing 
a match or search. If you have the option, prefer to compile a pattern 
into a basic_regex<> object once and reuse it rather than recreating 
it over and over.

Would it be feasible/advantageous for the regex-related libraries to 
automagically to "cache" the immediately previous regex compilation? 
(or provide as an option)

I've seen code that had the same regex being compiled inside a loop, 
which I suppose would really diminish performance. Perhaps this could 
be detected, and the user/developer "protected from themselves" ... 
and/or perhaps informed that this is happening?

Could there be a "helper" class that somehow or other allowed the last 
"n" regexes to be cached? (btw .... what is the plural of regex .... 
regexen?  regices?)

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