On Fri, 2008-02-29 at 18:27 +0100, Christian Schneider wrote:
> Marcus Boerger wrote:
> > you still cannot ignore basic inheritance or reuse rules. Protocols
> > have to be respected -> E_FATAL, fix your code.
I don't see why THIS protocol should need to be respected when PHP lacks
argument signature support (thus allowing method overloading). This used
to be something that was flexible in PHP4 but now you can't modify the
args signature downstream despite the obvious lack of method
overloading. Shackles abound that once didn't exist. Using
func_get_args() to simulate this is a gut wrenching experience of sloppy
necessity. "Fix your code" isn't very constructive... one could fire
back "fix the engine" :/
Cheers,
Rob.
>
> I have several comments (plus patches) to this:
>
> 1) The current checks are IMHO too strict regarding default values for
> parameters: An inheriting class can add default values to a parameter
> without breaking the protocol:
> class A { function foo($x) { ... } }
> class B extends A { function foo($x = 42) { ... } }
> should be allowed. Only if there are fewer parameters in B::foo or if
> B::foo has more *required* parameters than A::foo the protocol is
> broken. Otherwise every instance of B can be passed to something
> expecting A.
> The attached paramcheck_relaxed.patch.txt for HEAD changes this.
>
> 2) The current checks are IMHO too strict regarding static functions:
> Static functions are not part of an instance's protocol (they can not be
> passed around) and should be left out of the check the same way
> constructors are ignored. The use case for this is a factory method:
> class A { static function factory($size) { ... } }
> class B extends A { static function factory($size, $color) { ... } }
> The attached paramcheck_relaxed.patch.txt for HEAD changes this.
>
> 3) I guess more controversial is the change from E_STRICT to
> E_COMPILE_ERROR for PHP 6 regarding these checks. While you consider
> such OO code as broken I would highly appreciate it if you recognize
> that other people have other coding standards and/or old code to
> maintain. Adhering to the
> http://en.wikipedia.org/wiki/Liskov_substitution_principle is something
> strict OO coders want to do. And they are using E_STRICT anyway, so I
> see no reason to force everybody else to change their code, so it should
> be left a simple E_STRICT IMHO.
> The attached paramcheck_e_strict.patch for HEAD changes this back to the
> old behaviour.
>
> If paramcheck_relaxed.patch.txt gets accepted I'd volunteer to back-port
> it to 5.x as well.
>
> Regards,
> - Chris
> plain text document attachment (paramcheck_relaxed.patch.txt)
> Index: Zend/zend_compile.c
> ===================================================================
> RCS file: /repository/ZendEngine2/zend_compile.c,v
> retrieving revision 1.804
> diff -u -r1.804 zend_compile.c
> --- Zend/zend_compile.c 23 Feb 2008 21:24:18 -0000 1.804
> +++ Zend/zend_compile.c 29 Feb 2008 16:26:51 -0000
> @@ -2477,12 +2477,12 @@
> }
>
> /* Checks for constructors only if they are declared in an interface */
> - if ((fe->common.fn_flags & ZEND_ACC_CTOR) &&
> !(proto->common.scope->ce_flags & ZEND_ACC_INTERFACE)) {
> + if ((fe->common.fn_flags & (ZEND_ACC_CTOR | ZEND_ACC_STATIC)) &&
> !(proto->common.scope->ce_flags & ZEND_ACC_INTERFACE)) {
> return 1;
> }
>
> /* check number of arguments */
> - if (proto->common.required_num_args != fe->common.required_num_args
> + if (proto->common.required_num_args < fe->common.required_num_args
> || proto->common.num_args > fe->common.num_args) {
> return 0;
> }
> plain text document attachment (paramcheck_e_strict.patch.txt)
> Index: Zend/zend_compile.c
> ===================================================================
> RCS file: /repository/ZendEngine2/zend_compile.c,v
> retrieving revision 1.804
> diff -u -r1.804 zend_compile.c
> --- Zend/zend_compile.c 23 Feb 2008 21:24:18 -0000 1.804
> +++ Zend/zend_compile.c 29 Feb 2008 17:23:45 -0000
> @@ -2617,7 +2617,7 @@
> child->common.prototype = parent->common.prototype ?
> parent->common.prototype : parent;
> }
>
> - if (child->common.prototype) {
> + if (child->common.prototype &&
> (child->common.prototype->common.fn_flags & ZEND_ACC_ABSTRACT)) {
> if (!zend_do_perform_implementation_check(child,
> child->common.prototype TSRMLS_CC)) {
> zend_error(E_COMPILE_ERROR, "Declaration of %v::%v()
> must be compatible with that of %v::%v()", ZEND_FN_SCOPE_NAME(child),
> child->common.function_name, ZEND_FN_SCOPE_NAME(child->common.prototype),
> child->common.prototype->common.function_name);
> }
>
> --
> PHP Internals - PHP Runtime Development Mailing List
> To unsubscribe, visit: http://www.php.net/unsub.php
--
.------------------------------------------------------------.
| InterJinn Application Framework - http://www.interjinn.com |
:------------------------------------------------------------:
| An application and templating framework for PHP. Boasting |
| a powerful, scalable system for accessing system services |
| such as forms, properties, sessions, and caches. InterJinn |
| also provides an extremely flexible architecture for |
| creating re-usable components quickly and easily. |
`------------------------------------------------------------'
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
