Introduction
Anonymous functions (also called lambda) return object of Closure class. This class has some additional methods that provide further control over anonymous functions.
Syntax
Closure { /* Methods */ private __construct ( void ) public static bind ( Closure $closure , object $newthis [, mixed $newscope = "static" ] ) : Closure public bindTo ( object $newthis [, mixed $newscope = "static" ] ) : Closure public call ( object $newthis [, mixed $... ] ) : mixed public static fromCallable ( callable $callable ) : Closure }
Methods
private Closure::__construct ( void ) — This method exists only to disallow instantiation of the Closure class. Objects of this class are created by anonymous function.
public static Closure::bind ( Closure $closure , object $newthis [, mixed $newscope = "static" ] ) − Closure — Duplicates a closure with a specific bound object and class scope. This method is a static version of Closure::bindTo().
public Closure::bindTo ( object $newthis [, mixed $newscope = "static" ] ) − Closure — Duplicates the closure with a new bound object and class scope. Creates and returns a new anonymous function with the same body and bound variables, but with a different object and a new class scope.
public Closure::call ( object $newthis [, mixed $... ] ) − mixed — Temporarily binds the closure to newthis, and calls it with any given parameters.
Closure Example
<?php class A { public $nm; function __construct($x){ $this->nm=$x; } } // Using call method $hello = function() { return "Hello " . $this->nm; }; echo $hello->call(new A("Amar")). "\n";; // using bind method $sayhello = $hello->bindTo(new A("Amar"),'A'); echo $sayhello(); ?>
Output
Above program shows following output
Hello Amar Hello Amar