Please use [] to separate the separator choices. Please consider using \A and \Z to test the entire input string. I think you meant ? rather than * for the final optional section? '?' means optionally, while * means zero or more.

use feature ":5.14";
use warnings FATAL => qw(all);
use strict;
use Data::Dump qw(dump);

my @d = qw(26-04 26-04-12 26.04 26.04.12 30/8 30/08 30.08/12 1 12 aa a
+a/bb aa.c help);

say (/\A\d{2}[.-]\d{2}([.-]\d{2})?\Z/ ? "Matches for $_" : "FAILS for 
+$_" ) for @d;

[download]

Produces:

Matches for 26-04
Matches for 26-04-12
Matches for 26.04
Matches for 26.04.12
FAILS for 30/8
FAILS for 30/08
FAILS for 30.08/12
FAILS for 1
FAILS for 12
FAILS for aa
FAILS for aa/bb
FAILS for aa.c
FAILS for help

In reply to Re: Regexp problem by philiprbrenan
in thread Regexp problem by agaved

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