php-parser/lib/PhpParser/Node/Stmt/Namespace_.php

<?php

namespace PhpParser\Node\Stmt;

use PhpParser\Node;
use PhpParser\Error;

class Namespace_ extends Node\Stmt
{
    /** @var null|Node\Name Name */
    public $name;
    /** @var Node[] Statements */
    public $stmts;

    protected static $specialNames = array(
        'self'   => true,
        'parent' => true,
        'static' => true,
    );

    /**
     * Constructs a namespace node.
     *
     * @param null|Node\Name $name       Name
     * @param null|Node[]    $stmts      Statements
     * @param array          $attributes Additional attributes
     */
    public function __construct(Node\Name $name = null, $stmts = array(), array $attributes = array()) {
        parent::__construct($attributes);
        $this->name = $name;
        $this->stmts = $stmts;

        if (isset(self::$specialNames[strtolower($this->name)])) {
            throw new Error(
                sprintf('Cannot use \'%s\' as namespace name', $this->name),
                $this->name->getAttributes()
            );
        }

        if (null !== $this->stmts) {
            foreach ($this->stmts as $stmt) {
                if ($stmt instanceof self) {
                    throw new Error('Namespace declarations cannot be nested', $stmt->getAttributes());
                }
            }
        }
    }

    public function getSubNodeNames() {
        return array('name', 'stmts');
    }
}