Re: Comparing hash table objects

[Sam Steingold]

> * Stefan Monnier <zbaavre@veb.hzbagerny.pn> [2022-06-13 09:02:41 -0400]:
>
> Sam Steingold [2022-06-12 19:55:08] wrote:
>> The way Python does it could be a good starting point:
>> unless a class defines __eq__ method, the comparison is Lisp eq.
>> So, if a class has structure, it should define the comparison method.
>> See https://docs.python.org/3/reference/datamodel.html#object.__eq__
>
> Seems like the exact same way ELisp works.

including for user-defined classes?!

> The problem we have right now (translated into Python) is that some

please use ELisp terminology too for those who will want to read the sources.

> people now want to add a `__eq__` method to the class `hash-table`
> (they argue that the lack of it was an oversight).

sounds about right.

> It's easy to do what they ask for, but it breaks backward
> compatibility.

I would argue that code relying on `equal' being the same as `eq' for
`hash-table' is a bug.  Exposing such a bug might be painful, but it
should be fixed anyway.

Thank you for your clarifications.

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