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Date: Wed, 19 Oct 2011 09:18:41 +0800
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Subject: Re: [PHP-DEV] is_a fix for 5.4 and HEAD
From: alan@akbkhome.com (Alan Knowles)

Supporting strings 'by default' in is_a() has the downside that it 
produces slightly unpredictable results. If you are accepting 'mixed' 
arguments, some of which may be strings, there is a slim chance that the 
string you accept will match the class or it's parent by accident.

Personally if I did not believe that the barrier for a  BC change has to 
be alot higher than 'prettier or consistent API', i would have suggested 
that is_subclass_of should be changed to be 'consistent', and safer.

While the old justification for using is_a() over instanceof, has almost 
gone (it was the only way to write code that was portable to  PHP4 & 
PHP5.*, except for the annoying depreciation message). I still consider 
is_a(), especially with negative testing slightly clearer to read than 
instanceof.

Regards
Alan

On Monday, October 17, 2011 09:22 PM, Jonathan Bond-Caron wrote:
> On Sun Oct 16 06:59 PM, Stas Malyshev wrote:
>> It definitely makes PHP worse by propagating inconsistent APIs.
> I created a patch against 5.4:
> https://bugs.php.net/patch-display.php?bug_id=55475&patch=is_a_5.4_alternati
> ve&revision=latest
>
> The patch changes the behavior to:
> is_a("ab", "b") // false
> is_a("ab", "b", true) // autoload "ab", autoload "b" -- false
>
> is_subclass_of("ab", "b") // false
> is_subclass_of("ab", "b", true) // autoload "ab", autoload "b" -- false
>
> Both class names can be "autoloaded" but not by default
>
> Thoughts?
>
>
>