__return_zero() WP 3.0.0

Simply returns 0. Helper function of WordPress. Useful for use in filters.

All such helper functions:
__return_false() — returns false.
__return_true() — returns true.
__return_empty_array() — returns an empty: array().
__return_zero() — returns the number 0.
__return_null() — returns NULL.
__return_empty_string() — returns an empty string: ''.

1 time = 0.000001s = speed of light | 50000 times = 0.00s = speed of light | PHP 7.1.11, WP 4.9.7

No Hooks.

Return

Int. 0.

Usage

__return_zero() // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.FunctionDoubleUnderscore;

Examples

#1 Example of how to use function

Suppose we need return 0 in filter example_filter. Use this code:

add_filter( 'my_filter', '__return_zero' );

The same can be written in a different way:

// anonymous function (php 5.3+)
add_filter( 'my_filter', function(){ return 0; } );

// or so, with function registration 
add_filter( 'my_filter', 'my_return_function' );
function my_return_function(){
	return 0;
}

Changelog

Since 3.0.0

Introduced.

Code of `__return_zero() return zero` ^{WP 5.5.1}

wp-includes/functions.php

<?php
function __return_zero() { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.FunctionDoubleUnderscore
	return 0;
}

From tag: __return (helper functions)

__return_true()