Opis Closure

Installation, licensing and requirements

This version of the library is no longer maintained. Please consider upgrading to the latest release

Opis Closure is a library that aims to overcome PHP’s limitations regarding closure serialization by providing a wrapper that will make all closures serializable.

The library’s key features:

  • Serialize any closure
  • Doesn’t use eval for closure serialization or unserialization
  • Works with any PHP version that has support for closures (Yes, even with PHP 5.3)
  • Supports PHP 7.0 syntax
  • Handles all variables referenced/imported in use() and automatically wraps all referenced/imported closures for proper serialization
  • Handles recursive closures
  • Handles magic constants like __FILE__, __DIR__, __LINE__, __NAMESPACE__, __CLASS__, __TRAIT__, __METHOD__ and __FUNCTION__
  • Automatically resolves all class names used inside the closure
  • Track closure’s residing source by using the #trackme directive
  • Simple and very fast parser
  • Any error or exception, that might occur when executing an unserialized closure, can be caught and treated properly
  • You can serialize/unserialize any closure unlimited times, even those previously unserialized (this is possible because eval() is not used for unserialization)
  • Handles static closures
  • Supports cryptographically signed closures
  • Provides a reflector that can give you information about the serialized closure
  • Provides an analyzer for SuperClosure library
  • Automatically detects when the scope and/or the bound object of a closure needs to be serialized in order for the closure to work after deserialization


Opis Closure is licensed under the MIT License (MIT).


  • PHP 5.3.0 or higher


Opis Closure is available on Packagist and can be installed using Composer.

    "require": {
        "opis/closure": "^2.4.0"

If you are unable to use Composer you can download the .tar.gz or the .zip archive file, extract the content of the archive and include de autoload.php file into your project.

require_once 'path/to/opis/closure-2.4.0/autoload.php';

SuperClosure support

Starting with version 2.2.0, Opis Closure is shipped with an analyzer(Opis\Closure\Analyzer) which aims to provide Opis Closure’s parsing precision and speed to SuperClosure.


Due to PHP limitations, the Opis Closure library cannot detect the correct closure code if there is more then one closure on a single line.

// This will NOT work!
$first = function() {return "1st";}; $second = function() {return "2nd";};

// This will work!
$first = function() {return "1st";};
$second = function() {return "2nd";};