Use ? To indicate a character that can appear zero or one time.

For example:

$ perl -e "print '2000-20-30' =~ /\d{4}-?\d{2}-?\d{2}/"
1

$ perl -e "print '20002030' =~ /\d{4}-?\d{2}-?\d{2}/"
1

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In reply to Re: simple regexp question by osunderdog
in thread simple regexp question by jeanluca

Title:
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