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Subject: Re: [PHP-DEV] [VOTE] Userspace operator overloading
From: ajf@ajf.me (Andrea Faulds)
Message-ID: <php.internals-109404@news.php.net>

Hi,

Christoph M. Becker wrote:
> (frankly, I would not have not supported __concat() at all).  Also,
> overloaded operators should be programmed defensively, i.e. they should
> not accept arbitrary arguments (how could that even work?), but only
> those they can handle.  If implementations adhere to these "rules", I
> don't see real issues.

Consider a type implementing some kind of list. Perhaps someone would 
want to overload the + operator to mean adding an item to the list. If 
the list accepts any type of value as a valid item, then you have an 
example of an unconditional overload.

Regards,
Andrea