Re: [PATCH] Implement `equal' for hash tables

Björn A. Lindqvist [14/Aug  9:27pm +02] wrote:
> On 8/14/26 13:13, Sean Whitton wrote:
>> I think we'd really like to see examples.  I don't think I have ever
>> done it so I have a hard time believing "extremely"
>
> Suppose you have same JSON configuration. The most natural
> representation of it is a list of hash tables that contain nested hash
> tables and lists. You perform some expensive operation only if the
> configuration changes:
>
> (when (not (equal old-config new-config))
>    (expensive-op))
>
> The configuration may be a parse tree, key-value store, or any other
> kind of database for which nested hash tables is a convenient
> representation.

Oh, interesting example, thanks.

Stefan, what do you think of this?

>>> To the best of my knowledge, there is not a single programming
>>> language which distinguishes between equality and identity created
>>> since Java that does not support comparing hash tables for
>>> equality.
>>
>> Looks like Python has it.  Perl doesn't.
>
> Perl is ancient. My point is that if everyone is doing X and you are
> doing Y, it may be worth considering whether you also should do X
> instead of Y.

(Python is older than Perl :))

-- 
Sean Whitton