First try with Perl::Critic. According to cpan here, the latest version of Readonly is 1.03. How do I get rid of the Readonly error along with the rest of them:

package CriticMy;

use strict;
use warnings;
use 5.010;

use criticism 'gentle';
use Readonly my $unprintable => 0x15;    #***LINE 8*****

our $VERSION = 1.00;

1;

--output:--
Use of uninitialized value $_ in pattern match (m//) at /Users/7stud/p
+erl5/perlbrew/perls/perl-5.16.0/lib/5.16.0/Exporter.pm line 57.
Use of uninitialized value $_ in exists at /Users/7stud/perl5/perlbrew
+/perls/perl-5.16.0/lib/5.16.0/Exporter.pm line 57.
Use of uninitialized value $_ in pattern match (m//) at CriticMy.pm li
+ne 8.
Use of uninitialized value $sym in hash element at CriticMy.pm line 8.
Use of uninitialized value $sym in pattern match (m//) at CriticMy.pm 
+line 8.
Use of uninitialized value $sym in substitution (s///) at CriticMy.pm 
+line 8.
Use of uninitialized value $sym in hash element at CriticMy.pm line 8.
Use of uninitialized value $sym in concatenation (.) or string at Crit
+icMy.pm line 8.
Readonly version 21 required--this is only version 1.03 at /Users/7stu
+d/perl5/perlbrew/perls/perl-5.16.0/lib/5.16.0/Exporter/Heavy.pm line 
+120.
BEGIN failed--compilation aborted at CriticMy.pm line 8.

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In reply to Perl::Critic error "Readonly version 21 required" by 7stud

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