greencape/repl

A generic Read-Eval-Print Loop for PHP

1.0.0 2023-03-20 10:57 UTC

Requires (Dev)

• phpunit/phpunit: ^10.0

MIT

• Niels Braczek

README

GreenCape REPL is a simple Read-Eval-Print Loop (REPL) written in PHP. It can be combined with arbitrary evaluators for the Eval step.

Installation

composer require greencape/repl

Usage

Create an Evaluator implementing the GreenCape\REPL\EvaluatorInterface and pass it to the REPL:

use GreenCape\REPL\EvaluatorInterface;
use GreenCape\REPL\ReadEvalPrintLoop;

class MyEvaluator implements EvaluatorInterface
{
    public function init(): void {}
    public function exit(): void {}
    public function eval(string $input): string
    {
        // Handle the input and return the result
        return $result;
    }
}

$evaluator = new MyEvaluator();
$repl      = new ReadEvalPrintLoop($evaluator);

$repl->run();

With init() and exit() you can implement a setup and teardown for the REPL.

The loop will read your input after a '> ' prompt' and send it to the eval() method of the Evaluator. The result will be printed to the console. You can enter multi line input by ending each line with a backslash. Continuation lines are indicated by a '>> ' prompt.

To terminate the loop, enter exit.