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Oh, \K doesn't stop .* from matching the entire string. Perl is smart enough to back off to the last "." when the \. node comes up.

What \K is doing is faking WHERE in the string (and the pattern) the regex started to match. Compare:

$str = "Match 9 the 1 last 6 digit 2 blah"; $str =~ /.*\d/; print "[$`] [$&] [$']\n"; $str =~ /.*\K\d/; print "[$`] [$&] [$']\n"; __END__ [] [Match 9 the 1 last 6 digit 2] [ blah] [Match 9 the 1 last 6 digit ] [2] [ blah]
See, \K tells $& that THIS is where it begins. This is useful in substitutions:
# you go from this: s/(saveme)deleteme/$1/; # to this: s/saveme\Kdeleteme//;
And you save time on replacing "saveme" with itself.

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 Re: Re: Re: Re: New regex trick... by japhy
in thread New regex trick... by japhy

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