Perl::Critic::Policy::Bangs::ProhibitRefProtoOrProto - Create a clone() method if you need copies of objects.
clone()
This Policy is part of the Perl::Critic::Bangs distribution.
Many times you'll see code for object constructors that's been cut-and-pasted from somewhere else, and it looks like this:
sub new { my $proto = shift; my $class = ref($proto) || $proto; my $self = bless {}, $class; ... }
The $class is derived from the first parameter, whether it's the class name, or an existing object. This lets you do this:
$class
my $fido = Dog->new();
which is very common, and the less likely
my $rover = $fido->new();
Now, why would you want to instantiate an object based on the type of another object? If you want to make $rover a clone of $fido, then Dog should have a clone() method, instead of overloading the meaning of new().
$rover
$fido
new()
That's all the ref($proto) || $proto does for you. If you don't need that dubious functionality, then write your constructors like this:
ref($proto) || $proto
sub new { my $class = shift; my $self = bless {}, $class; }
See also Randal Schwartz's take on it at http://www.stonehenge.com/merlyn/UnixReview/col52.html.
This Policy is not configurable except for the standard options.
Andrew Moore <amoore@mooresystems.com>
Adapted from policies by Jeffrey Ryan Thalhammer <thaljef@cpan.org>, and work done by Andrew Moore <amoore@mooresystems.com>.
Copyright (C) 2006-2011 Andy Lester
This library is free software; you can redistribute it and/or modify it under the terms of the Artistic License 2.0.
To install Perl::Critic::Bangs, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Perl::Critic::Bangs
CPAN shell
perl -MCPAN -e shell install Perl::Critic::Bangs
For more information on module installation, please visit the detailed CPAN module installation guide.