On Tue, Feb 26, 2013 at 7:41 AM, Dmitry Stogov <[email protected]> wrote:
> Hi Nikita,
>
> I like the idea.
> But note, that it may cause some unexpected behaviour and bugs.
> I didn't test the patch I just guess it on my previous experience
> introducing similar features.
>
> - usage expression in write context (e.g. passing constant by reference)
>
> function foo(&$foo) {}
> foo("abc"[0]);
>
> - destruction of temporary result
>
> ($a . $b)[4]; // if ($a.$b) is destroyed?
>
> - in some cases destruction of temporary result may cause destruction of
> final result
>
> ((object)(array("a"=>"b")))->a = "c"; // temporary object
> may be destroyed
> before assignment
>
> All these edge cases must be carefully analyzed.
> I like the current patch, and in case the edge cases won't require many
> hacks, I'm all for it.
>
> Thanks. Dmitry.
>
All these edge-cases are covered by not being allowed :) The old (new
Foo)->bar syntax did not allow usage as a variable and I stayed with that.
I.e. (expr)->xyz will still be an expression, not a variable and as such
(expr)->xyz = 'foo' will be a syntax error.
I stayed with the old behavior because I thought that it would just be a
small bugfix-like change that way, whereas allowing usage in write-context
could require larger changes (though I haven't tried, maybe its just as
simple). But now that everybody seems to think that this is a major change
that requires serious consideration, I guess I can have a look at the
write-context use too :)
Nikita