Offset.php

<?php declare(strict_types=1);

namespace Kiboko\Component\ETL\ExpressionLanguage\Akeneo;

use Symfony\Component\ExpressionLanguage\ExpressionFunction;

final class Offset extends ExpressionFunction
{
    public function __construct($name)
    {
        parent::__construct(
            $name,
            \Closure::fromCallable([$this, 'compile'])->bindTo($this),
            \Closure::fromCallable([$this, 'evaluate'])->bindTo($this)
        );
    }

    private function compile(string $offset)
    {
        return sprintf('function(array $input) {return array_slice($input, %s, null, true);}', $offset);
    }

    private function evaluate(array $context, int $offset)
    {
        return function(array $input) use($offset) {
            return array_slice($input, $offset, null, true);
        };
    }
}