I've got a new regex trick up my sleeve, and although I'm proposing a patch for it, I'm not sure it'll be accepted. It's a new pseudo-anchor, \K, which tells the engine to pretend it just started matching. That's not a very good explanation, so let me use an example: 
# code to remove '.z' from $str

# old way (slow)
$str = join '.', 'a' .. 'z';
$str =~ s/(.*)\..*/$1/;

# new way (fast)
$str = join '.', 'a' .. 'z';
$str =~ s/.*\K\..*//;

[download]
I'll post more soon, when I have a patch and what-not, but I hope this gives you a good idea of what this anchor does.

Another way of looking at it is it lets you have a variable-width look-behind at the beginning of your regex... it allows your regex to have a prelude, as it were.

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to New regex trick... by japhy

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