bug#50214: 28.0.50; cl-struct changes may affect user packages in the wild

[Adam Porter <adam@alphapapa.net>]

Hi Lars,

Thanks for following up on this report.

On 8/22/22 09:35, Lars Ingebrigtsen wrote:
> Philipp <p.stephani2@gmail.com> writes:
> 
>>> Unfortunately, I know of no other way to implement what ts.el does
>>> without modifying the accessors, which requires accessing the internal
>>> struct details after it is defined.
>>
>> I haven't checked the code in detail, but AIUI ts.el tries to initialize structure members lazily?  Why not just use a wrapper function for that?
>>
>> (defun ts-hour (ts)
>>    (or (ts--hour ts)
>>        (setf (ts--hour ts) (string-to-number (format-time-string "%H" (ts-unix ts)))))
>>
>> Here ts--hour is the actual accessor, which is private and shouldn't be used outside of ts.el.
> 
> Adam, does this suggestion work for you?

That seems like a good idea to me.  I guess if I define it as an inline 
function, it should have a similar optimization as the current code. 
And the implementation would be much simpler and future-proof as well. 
In hindsight, I should probably have tried that first.  :)

I'll see if I can implement this in ts.el soon and release a new version 
accordingly.  In the meantime, I guess this bug report should be closed. 
  Thanks to all for your help.

Adam