http://www.perlmonks.org?node_id=11105131


in reply to Re^4: regex return true instead of false (precedence)
in thread regex return true instead of false

Also you can waste one line of code for making first conditional to have the same line-format as others:
if( not 0 || $args =~ /\-rs(\s+)(\S+)/x # || $args =~ /\-? (\s+)(\S+)/x || $args =~ /\-p (\s+)(\S+)/x || $args =~ /\-P (\s+)(\S+)/x ){ ... }
...or equivalently inside regex:
if( $args !~ / (*FAIL) | \-rs(\s+)(\S+) # | \-? (\s+)(\S+) | \-P (\s+)(\S+) | \-p (\s+)(\S+) /x ){ ... }
edit: not equivalently, because there are 8 capturing groups instead of 2 :)

Of course regex can be simplyfied as AnomalousMonk have shown here Re: regex return true instead of false.