PHP-Parser/lib/PhpParser/Builder/FunctionLike.php

<?php declare(strict_types=1);

namespace PhpParser\Builder;

use PhpParser\BuilderHelpers;
use PhpParser\Node;

abstract class FunctionLike extends Declaration
{
    protected $returnByRef = false;
    protected $params = [];

    /** @var string|Node\Name|Node\NullableType|null */
    protected $returnType = null;

    /**
     * Make the function return by reference.
     *
     * @return $this The builder instance (for fluid interface)
     */
    public function makeReturnByRef() {
        $this->returnByRef = true;

        return $this;
    }

    /**
     * Adds a parameter.
     *
     * @param Node\Param|Param $param The parameter to add
     *
     * @return $this The builder instance (for fluid interface)
     */
    public function addParam($param) {
        $param = BuilderHelpers::normalizeNode($param);

        if (!$param instanceof Node\Param) {
            throw new \LogicException(sprintf('Expected parameter node, got "%s"', $param->getType()));
        }

        $this->params[] = $param;

        return $this;
    }

    /**
     * Adds multiple parameters.
     *
     * @param array $params The parameters to add
     *
     * @return $this The builder instance (for fluid interface)
     */
    public function addParams(array $params) {
        foreach ($params as $param) {
            $this->addParam($param);
        }

        return $this;
    }

    /**
     * Sets the return type for PHP 7.
     *
     * @param string|Node\Name|Node\NullableType $type One of array, callable, string, int, float,
     *                                                 bool, iterable, or a class/interface name.
     *
     * @return $this The builder instance (for fluid interface)
     */
    public function setReturnType($type) {
        $this->returnType = BuilderHelpers::normalizeType($type);

        return $this;
    }
}