<?php
/**
* The Singleton Trait can be used to wrap an execution block, so it behaves like a Singleton.
* It executes the callable once, on subsequent calls returns the same result.
*/
namespace WooCommerce\PayPalCommerce\Common\Pattern;
/**
* Class SingletonDecorator.
*/
class SingletonDecorator
{
/**
* The callable with the executing code
*
* @var callable
*/
private $callable;
/**
* The execution result
*
* @var mixed
*/
private $result;
/**
* Indicates if the callable is resolved
*
* @var bool
*/
private $executed = \false;
/**
* SingletonDecorator constructor.
*
* @param callable $callable
*/
public function __construct(callable $callable)
{
$this->callable = $callable;
}
/**
* The make constructor.
*
* @param callable $callable
* @return self
*/
public static function make(callable $callable): self
{
return new static($callable);
}
/**
* Invokes a callable once and returns the same result on subsequent invokes.
*
* @param mixed ...$args Arguments to be passed to the callable.
* @return mixed
*/
public function __invoke(...$args)
{
if (!$this->executed) {
$this->result = call_user_func_array($this->callable, $args);
$this->executed = \true;
}
return $this->result;
}
}