PHP Closure

main.php

<?php
class a {
	protected $hoge = 'foo';
}
$a = new a();
$closure = Closure::bind(function () {
	$this->hoge = 'foofoo';
}, $a, $a);
$closure();

$closure = Closure::bind(function () {
	echo $this->hoge . PHP_EOL;
}, $a, $a);
$closure();	//-> foofoo
?>

main2.php

<?php
class a {
	protected $hoge = 'foo';
	
	public function bind (Closure $closure, $closure_args=[]) {
		$ret = false;
		if (is_callable($closure)) {
			$closure = Closure::bind($closure, $this, $this);
			$ret = call_user_func_array($closure, $closure_args);
		}
		return $ret;
	}
}

$a = new a();
echo $a->bind(function ($field) {
	return $this->$field;
}, ['hoge']);	//<- foo
?>