Composer Repl Lib Laravel Package

Getting Started

Start by installing ramsey/composer-repl-lib via Composer in your tool or plugin:

composer require ramsey/composer-repl-lib

Then, instantiate the REPL builder in your command logic (e.g., inside a Symfony Console or Laravel command):

use Ramsey\Composer\Repl\ReplBuilder;

$repl = (new ReplBuilder())
    ->withBootstrapFile('vendor/autoload.php')
    ->build();

$repl->start();

The first use case is typically spinning up a REPL inside a custom CLI command to inspect Composer-installed dependencies, test autoloaded classes, or debug configLoading logic interactively.

Implementation Patterns

• Embed in custom CLI commands: Wrap the REPL in a Command::handle() method to offer developers a live environment without spawning a full shell.
• Preload context: Use withVariable('name', $value) to inject application state (e.g., $app, config, or factory instances) into the REPL scope.
• Customize evaluator: Implement EvaluatorInterface to tailor eval behavior (e.g., scope isolation, result formatting).
• Laravel integration: In a service provider, bind the REPL as a shared service and fire it on demand via php artisan my:repl command.
• Dynamic bootstrap: Generate on-the-fly bootstrap code (e.g., ->withBootstrapCode('$_env = $_ENV;')) to expose dynamic runtime state safely.

Gotchas and Tips

• Security: Avoid passing eval()-untrusted input—this library is for developer tooling, not production use.
• Autoload timing: Ensure vendor/autoload.php is included before the REPL starts—withBootstrapFile() assumes PSR-4/autoloading is ready.
• CLI stream quirks: On Windows, verify php_sapi_name() === 'cli'; some REPL internals (e.g., readline) may silently fall back to basic input.
• Silent eval: The REPL returns null for non-echoing expressions—use var_dump() or echo explicitly to inspect results.
• Extensibility point: Extend Evaluator to add macro functions or hook into debug output (e.g., add Xdebug-style tracing).
• No persistent state: Each start() invocation creates a fresh scope—store reusable snippets in ~/.composer-repl/config.php or your custom bootstrap.