Do not assign a variable to itself

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Metadata

ID: php-best-practices/no-self-assign

Language: PHP

Severity: Notice

Category: Error Prone

Description

This rule aims to prevent redundancy in code. Assigning a variable to itself is a pointless operation that can lead to confusion and clutter in the code, making it harder to read and understand. It’s also a potential indicator of a mistake or oversight in the code, where a different assignment was intended.

This rule is important because clean, efficient code is a hallmark of good programming. Unnecessary assignments can slow down the runtime of the script and, more importantly, make the code harder to maintain and debug. In a large codebase, such redundancies can add up to significant inefficiencies.

To avoid this, always ensure that the right-hand side of an assignment is not the same as the left-hand side. If you find yourself writing var = var, it’s probably a mistake. Double-check your code to ensure that you’re assigning the correct variables. If you’re reassigning a variable to itself intentionally, consider whether this is really necessary and if there might be a cleaner way to achieve your goal.

Non-Compliant Code Examples

<?php
$var = 1;
$var2 = 2;
$var = $var;

Compliant Code Examples

<?php
$var = 1;
$var2 = 2;
$var = $var2;