Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:57262
Return-Path: <sebastian@php.net>
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Delivered-To: mailing list internals@lists.php.net
Received: (qmail 97710 invoked from network); 7 Jan 2012 09:31:24 -0000
Received: from unknown (HELO lists.php.net) (127.0.0.1)
  by localhost with SMTP; 7 Jan 2012 09:31:24 -0000
Authentication-Results: pb1.pair.com smtp.mail=sebastian@php.net; spf=unknown; sender-id=unknown
Authentication-Results: pb1.pair.com header.from=sebastian@php.net; sender-id=unknown
Received-SPF: unknown (pb1.pair.com: domain php.net does not designate 93.190.64.33 as permitted sender)
X-PHP-List-Original-Sender: sebastian@php.net
X-Host-Fingerprint: 93.190.64.33 mail-3.de-punkt.de  
Received: from [93.190.64.33] ([93.190.64.33:57240] helo=mail-3.de-punkt.de)
	by pb1.pair.com (ecelerity 2.1.1.9-wez r(12769M)) with ESMTP
	id 90/C0-25923-9E0180F4 for <internals@lists.php.net>; Sat, 07 Jan 2012 04:31:23 -0500
Received: (qmail 23181 invoked by uid 511); 7 Jan 2012 09:31:18 -0000
Received: by simscan 1.4.0 ppid: 23177, pid: 23179, t: 0.0511s
         scanners: attach: 1.4.0
Received: from unknown (HELO ?0.0.0.0?) (sb%sebastian-bergmann.de@217.114.76.105)
  by 0 with ESMTPA; 7 Jan 2012 09:31:18 -0000
Message-ID: <4F0810E7.2050904@php.net>
Date: Sat, 07 Jan 2012 10:31:19 +0100
Reply-To: internals@lists.php.net
Organization: PHP Development Team
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0
MIME-Version: 1.0
To: internals@lists.php.net
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Subject: "Cannot use $this as lexical variable" message still in PHP 5.4
From: sebastian@php.net (Sebastian Bergmann)

  While

     <?php
     class a {
         public function b() {
             $f = function () {
                 $this->c();
             };
         }
     }

  compiles as expected with PHP 5.4, the following

     <?php
     class a {
         public function b() {
             $f = function () use ($this) {
                 $this->c();
             };
         }
     }

  results in

    Fatal error: Cannot use $this as lexical variable in ...

  This is because

     void zend_do_fetch_lexical_variable(znode *varname,
     zend_bool is_ref TSRMLS_DC) /* {{{ */
     {
         znode value;

         if (Z_STRLEN(varname->u.constant) == sizeof("this") - 1 &&
             memcmp(Z_STRVAL(varname->u.constant), "this",
             sizeof("this") - 1) == 0) {
             zend_error(E_COMPILE_ERROR, "Cannot use $this as lexical
             variable");
             return;
         }

  is still in zend_compile.c. IIRC, this code was added in PHP 5.3 to
  prevent $this from being used as a lexical variable. It should no
  longer be required in PHP 5.4. Right?

-- 
Sebastian Bergmann                    Co-Founder and Principal Consultant
http://sebastian-bergmann.de/                           http://thePHP.cc/