package MyValidate; # use package to declare a module
our $val;

sub val_time {
    $val = shift;
    $val = ($val =~ /^(\d{2}):(\d{2}) (am|pm)$/) ? "$1:$2 $3" : 1;
}

1;

##</code><code>##

package MyValidate; # use package to declare a module

sub val_time {
    my $val = shift;
    $val = ($val =~ /^(\d{2}):(\d{2}) (am|pm)$/) ? "$1:$2 $3" : 1;
    return $val; # yes this is not necessary but it clarifies my intension
}

1;