Not particularly elegant, but fairly clean: 
sub convert_format
{
    my $format = shift;
    # If we have a 4 digit year
    $format =~ s/9999/YYYY/;
    # Two cases:
    if ($format =~ /^Y/) {
        # Month first
        $format =~ s/99/MM/;
        $format =~ s/99/DD/;
    }
    else {
        # Day first
        $format =~ s/99/DD/;
        $format =~ s/99/MM/;
    }
    # Handle two digit year
    $format =~ s/99/RR/;
    return $format;
}

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In reply to Re: Generating a format template for a date by jbert
in thread Generating a format template for a date by bart

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