Following the pronciple of KISS 

my $s = '2003 % 05 % 1720:55:23';

$s =~ s[(....) % (..) % (..).*][$1-$2-$3]; 
print $s;

2003-05-17

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Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller

In reply to Re: Regex to parse a date by BrowserUk
in thread Regex to parse a date by MD

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