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Date: Mon, 23 Oct 2023 17:14:20 +0200
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Subject: Re: [PHP-DEV] Custom object equality
From: dik.takken@gmail.com (Dik Takken)

On 18-10-2023 14:50, someniatko wrote:
> This approach allows combining
> - no BC break - `~=` is a new syntax which is unavailable in older PHP
> versions
> - explicitly showing an intent that objects are compared using a custom
> comparison, rather than standard PHP one
> - allow to skip writing boilerplate equals() methods which just forward
> equals() to the nested objects
> - standardize such comparisons on the language level
> 
> Of course how exactly this operator looks may be changed, `~=` is just an
> example.
> 
> WDYT?
> 
> Regards,
> Illia / someniatko
> 

One thing to keep in mind is that operator overloading already exists in 
PHP. And it is already in use in userland PHP too, for example when 
comparing DateTime objects. The limitation is that it only works for 
some objects: Those that are implemented in an extension.

To me, the obvious way forward would be to lift this limitation. But... 
several attempts to do so have failed to pass. People are hesitant to 
unleash full operator overloading power to PHP developers.

So, perhaps a simplified version of the RFC by Jordan LeDoux, limited to 
the `==` operator only, would stand a chance? It would allow the 
community to try their hands on this one (highly valuable) operator 
overload. PHP 9 is coming and provides a great opportunity.

I also like the idea from Pierre to provide interfaces. Some people 
prefer an explicit method call over an operator doing magic things, 
which I fully understand. Perhaps we could allow both?

Regards,
Dik