Callables

A callable is an object that can pass the callable type.

A callable may be a callback function or method, represented as a string, a closure or an arrow function.

Objects may also be callable, when their class implement the magic method __invoke().

<?php

function foo() { echo __METHOD__; }

call_user_func('foo');

?>

Documentation

See also What Is the callable Type in PHP?.

Related : Callbacks, Closure, __invoke() Method, Arrow Functions, Callable Arrays, Call, Pseudo-type, Special Types, Identity, PHP Natives