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Date: Mon, 23 Aug 2021 11:12:27 +0200
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Subject: Re: [PHP-DEV] Revisiting Userland Operator Overloads
From: dik.takken@gmail.com (Dik Takken)

On 08-08-2021 09:41, Jordan LeDoux wrote:
> Off the top of my head here are some of the use cases that I think benefit
> greatly from this:
> 
> - Complex number objects
> - Fractions objects
> - Matrix objects (math)
> - Vector objects (math)
> - Time/Date intervals
> - Collections
> - Arbitrary precision numbers (which are usually represented as a string in
> PHP)

Hi Jordan,

I would like to point out another interesting use case that I have seen
in the Python world: Query builders. In that use case, operator
overloads are used to create database filtering expressions for example,
allowing one to write:

db.products.filter(db.products.price < 100)

Here db.products.price is an object representing a database column
implementing the __lt__ method, overloading the < operator. This method
returns an object representing a database filtering expression, which
gets passed to the filter() method.

So basically, this would allow for writing expressions in plain PHP and
have them translated into other languages under the hood.

The use case does require that operator overloads are allowed to return
any kind of value they wish.

Regards,
Dik Takken