Properties are defined in a class, or created when needed during execution. Properties that are not used anywhere in the code are most likely useless. Such properties consume memory, use code space and may create confusion.
As a simple check, any property only used once in a context should be checked.
It is recommended to check that properties are used more than once in their class of definition.
This rule is aimed at eliminating unused variables or arguments.
The following patterns are considered warnings:
<?php
class foo {
private $unused = 2;
function bar() {
$this->assignedOnly = 2;
}
}
?>The following patterns are not considered warnings:
<?php
class foo {
public $used = 2;
function bar() {
$this->assignedOnly = 2;
}
}
$foo = new foo();
$foo->used = 4;
?>