README

The library behind the ramsey/composer-repl Composer plugin.

About

This is the library that powers the ramsey/composer-repl Composer plugin. Since you can't extend Composer plugins, this exists to allow for extension. This library also allows for non-plugin use of the repl CLI tool, which you may use even if you do not wish to use the plugin functionality.

Tip

If you don't need to extend this for your own plugin needs, and you want the functionality provided by the plugin, check out ramsey/composer-repl instead.

REPL stands for read-eval-print loop. It's a language shell that reads user input, evaluates the input using a programming language (in this case, PHP), and prints the output to the screen. Then, it returns to the read state (that's the loop part).

PsySH is the REPL providing the magic behind ramsey/composer-repl and ramsey/composer-repl-lib. PsySH is a language shell for PHP. It's similar to irb for Ruby, IPython for Python, and JShell for Java. In addition to acting as a language shell, PsySH can also function as an interactive debugger and development console. Laravel Tinker, Drush for Drupal, WP-CLI shell for WordPress, CakePHP console, and Yii shell are a few of the projects using PsySH.

This project adheres to a code of conduct. By participating in this project and its community, you are expected to uphold this code.

Installation

Install this package as a development dependency using Composer.

composer require --dev ramsey/composer-repl-lib

Usage

Open your terminal and type ./vendor/bin/repl.

You'll see something similar to this:

Psy Shell v0.12.20 (PHP 8.5.3 — cli) by Justin Hileman
------------------------------------------------------------------------
Welcome to the development console (REPL).
To learn more about what you can do in PsySH, type `help`.
------------------------------------------------------------------------
>>>

While in the dev console, you can do cool things like this:

> $hello = 'Hello, world'
= "Hello, world"

> echo $hello
Hello, world

> foreach ([1, 2, 3] as $x) echo $x . "\n"
1
2
3

> $date = new DateTimeImmutable();
= DateTimeImmutable @1772598406 {#359
    date: 2026-03-04 04:26:46.679771 UTC (+00:00),
  }

> $getDate = fn (DateTimeInterface $dt): DateTimeInterface => $dt;
= Closure(DateTimeInterface $dt): DateTimeInterface {#381 …3}

> t assertInstanceOf(DateTimeInterface::class, $date);
Test passed!

> t assertSame($date, $getDate($date))
Test passed!

> phpunit

PHPUnit 13.0.5 by Sebastian Bergmann and contributors.

Runtime:       PHP 8.5.3
Configuration: /path/to/ramsey/composer-repl-lib/phpunit.xml.dist

..................................SS....                          40 / 40 (100%)

Time: 00:00.288, Memory: 48.00 MB

OK, but some tests were skipped!
Tests: 40, Assertions: 105, Skipped: 2.

Important

✨🐘 This implementation of PsySH has Super ElePHPant Powers. 🐘✨

Environment Bootstrapping

The power of this REPL comes in its ability to act as a tool in your local development environment. So, you might want to load parts of your environment (i.e., configuration, objects, etc.), so you can access these from within the REPL.

You can do this by specifying any number of PHP scripts to include in composer.json, like this:

{
    "extra": {
        "ramsey/composer-repl": {
            "includes": [
                "repl.php",
                "tests/bootstrap.php"
            ]
        }
    }
}

Any variables set or configuration loaded from these scripts is available to use from within the REPL.

For example, if repl.php contains:

<?php
$foo = 'bar';

And we use composer.json to load it with the REPL:

{
    "extra": {
        "ramsey/composer-repl": {
            "includes": [ "repl.php" ]
        }
    }
}

Then, when we're in the REPL, we'll see $foo defined:

> ls
Variables: $env, $foo, $phpunit

> $foo
= "bar"

Contributing

Contributions are welcome! To contribute, please familiarize yourself with CONTRIBUTING.md.

Coordinated Disclosure

Keeping user information safe and secure is a top priority, and we welcome the contribution of external security researchers. If you believe you've found a security issue in software that is maintained in this repository, please read SECURITY.md for instructions on submitting a vulnerability report.

Copyright and License

The ramsey/composer-repl-lib library is copyright © Ben Ramsey and licensed for use under the terms of the MIT License (MIT). Please see LICENSE for more information.