---
name: "Perl::Critic::Policy::Variables::RequireInitializationForLocalVars"
section: "3pm"
platform: "linux"
package: "perl-perl-critic"
version: "1.156-3"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/Perl::Critic::Policy::Variables::RequireInitializationForLocalVars"
---

# Perl::Critic::Policy::Variables::RequireInitializationForLocalVars(3pm)

Write "local $foo = $bar;" instead of just "local $foo;".

## NAME

Perl::Critic::Policy::Variables::RequireInitializationForLocalVars - Write "local $foo = $bar;" instead of just "local $foo;".

## AFFILIATION

This Policy is part of the core Perl::Critic distribution.

## DESCRIPTION

Most people don't realize that a localized copy of a variable does not retain its original value.  Unless you initialize the variable when you `"local"`-ize it, it defaults to `"undef"`.  If you want the variable to retain its original value, just initialize it to itself. If you really do want the localized copy to be undef, then make it explicit.

```
    package Foo;
    $Bar = '42';
    package Baz;
    sub frobulate {
        local $Foo::Bar;              #not ok, local $Foo::Bar is 'undef'
        local $Foo::Bar = undef;      #ok, local $Foo::Bar is obviously 'undef'
        local $Foo::Bar = $Foo::Bar;  #ok, local $Foo::Bar still equals '42'
    }
```

## CONFIGURATION

This Policy is not configurable except for the standard options.

## AUTHOR

Jeffrey Ryan Thalhammer \<jeff@imaginative-software.com\>

## COPYRIGHT

Copyright (c) 2005-2011 Imaginative Software Systems.  All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.  The full text of this license can be found in the LICENSE file included with this module.