Here's a solution that uses the core module Time::Local 
use Time::Local qw( timegm );

/(\d{4})[-\/.](\d{2})[-\/.](\d{2})/
  or die("Bad format\n");

my $time = eval { timegm(0, 0, 0, $3, $2, $1) };
die("Bad date\n") if $@;

[download]
Switch timegm for timelocal if you prefer.

In reply to Re^2: regular expression help by ikegami
in thread regular expression help by Anonymous Monk

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