Control of unused variables in perl?

Question

Perl

Are there any solutions that will help in finding unused variables in the code?

Answer 1

use strict;
use warnings;
thus, all variables will need to be declared, and perl will issue a warning when a variable is mentioned only once in the code - this will mean that it is declared and not used.
In general, I've been using
use common::sense; lately.
Macro for a good set of directives .

Answer 2

Gives warning:
use warnings; $test_2=1; $test_1 = "hello\n"; print $test_1;
Does not give warning:
use warnings; my $test_2=1; $test_1 = "hello\n"; print $test_1;
2002 bug rt.perl.org/rt3/Public/Bug/Display.html?id=5087 bounty announced
in 2013 rjbs.manxome.org/rubric/entry/1964
Only perl can parse perl

Answer 3

Google search turned up Perl::Critic