bug#63513: [PATCH] Make persist-defvar work with records and hash tables

[Daniel Mendler]

On 9/9/23 12:01, Ihor Radchenko wrote:
> Joseph Turner <joseph@breatheoutbreathe.in> writes:
> 
>>> Then, wouldn't it be better to contribute this function to compat.el and
>>> use it from there?
>>
>> The new behavior of copy-tree has already been added to compat.el:
>>
>> https://github.com/emacs-compat/compat/pull/25
>>
>> However, that change currently only exists in compat's emacs-30 branch.
> 
> I see.
>
>> I did not know if it was acceptable for persist.el to require compat
>> when I wrote these patches. If we agree that it is acceptable, then I'm
>> happy to submit a patch to replace (persist-copy-tree ...) with
>> (compat-call copy-tree ...), but we'll have to wait to apply the patch
>> until after the compat.el emacs-30 branch is merged into master.
> 
> AFAIU, the recommended way to implement compat function definitions that
> are not yet added to compat.el is using `compat-defun' + `compat-call'.
> Then, one can simply drop `compat-defun' after the function is finally
> release with compat.el without touching the rest of the code.

`compat-call` is meant to be used to call "extended functions", for
example functions with additional arguments. See the Compat manual for
details.

The macros from compat-macs.el (`compat-defun` etc.) are internal as
documented in the file compat-macs.el. These macros must not be used
outside Compat.

So using Compat here has to wait until compat-30.x is released.

Daniel