PYTHON is_callable

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Python replacement for PHP's is_callable [ edit | history ] 
# Python 2.x and 3.2+:
callable(var)

# Python 3.0, 3.1
hasattr(var, "__call__")

PHP is_callable

PHP original manual for is_callable [ show | php.net ]

is_callable

(PHP 4 >= 4.0.6, PHP 5)

is_callable — Verify that the contents of a variable can be called as a function

Description

bool is_callable ( mixed $var [, bool $syntax_only= false [, string &$callable_name ]] )

Verify that the contents of a variable can be called as a function. This can check that a simple variable contains the name of a valid function, or that an array contains a properly encoded object and function name.

Parameters

var

Can be either the name of a function stored in a string variable, or an object and the name of a method within the object, like this:

array($SomeObject, 'MethodName')
syntax_only

If set to TRUE the function only verifies that var might be a function or method. It will only reject simple variables that are not strings, or an array that does not have a valid structure to be used as a callback. The valid ones are supposed to have only 2 entries, the first of which is an object or a string, and the second a string.

callable_name

Receives the "callable name". In the example below it is "someClass::someMethod". Note, however, that despite the implication that someClass::SomeMethod() is a callable static method, this is not the case.

Return Values

Returns TRUE if var is callable, FALSE otherwise.

Examples

Example #1 is_callable() example

<?php
//  How to check a variable to see if it can be called
//  as a function.

//
//  Simple variable containing a function
//

function someFunction() 
{
}

$functionVariable = 'someFunction';

var_dump(is_callable($functionVariable, false, $callable_name));  // bool(true)

echo $callable_name, "\n";  // someFunction

//
//  Array containing a method
//

class someClass {

  function someMethod() 
  {
  }

}

$anObject = new someClass();

$methodVariable = array($anObject, 'someMethod');

var_dump(is_callable($methodVariable, true, $callable_name));  //  bool(true)

echo $callable_name, "\n";  //  someClass::someMethod

?>

See Also

Variable handling Functions
PHP Manual