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PHP: is_callable() function

Description

The is_callable() function is used to test that the contents of a variable, whether it can be called as a function or not.

Version:

(PHP 4 and above)

Syntax:

is_callable(var_name, syntax_only, callable_name)

Parameters:

Name Description Required /
Optional
Type
var_name Either the name of a function stored in a string variable, or an object and the name of a method within the object. Required Mixed*
syntax_only If set to TRUE, the function only verifies if it is a function or a method. It rejects simple variables those are not strings and an array not having a valid structure. Optional Boolean
callable_name Receives a "callable name". This option is implemented only for classes. Optional String

*Mixed : Mixed indicates that a parameter may accept multiple (but not necessarily all) types.

Return value:

TRUE if var_name is callable, FALSE otherwise.

Value Type: Boolean.

Example :

<?php
function foo(){
}
echo is_callable('foo');
echo is_callable('bar');
?>

Output :

1

View the example in the browser

Practice here online :

See also

PHP Function Reference

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