while (<DATA>) {
    if ( /\d{4}-?(\d{3})\s{0,}?(\d\d:\d\d:\d\d)?/ ) {
        print "Match: $_" ;
    } else {
        print "NO MATCH: $_";
    }
}

__DATA__
2005-100 10:12:01
2005100 10:12:01
2005-100
2005100
2005

[download]
That only prints "NO MATCH" on the last line of input, and to fix that, you just need one more "?" in the regex: 
/\d{4}-?(\d{3})?\s{0,}?(\d\d:\d\d:\d\d)?/
#              ^--here

[download]

(updated code to fix indenting)

In reply to Re: regexp problem by graff
in thread regexp problem by jeanluca

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