Re: [BUG] org-capture autoload bug? [9.5.2 (9.5.2-gfbff08 @ /home/ignacio/.emacs.d/elpa/org-9.5.2/)]

[Ignacio Casso <ignaciocasso@hotmail.com>]

>>> For `defcustom' autoload generates no more than
>>>
>>>      (defvar org-capture-templates nil "...")
>>>
>>> It seems, behavior depends on whether `org-capture-templates' has the :set
>>> attribute.
>> Not really, all defcustoms have a :set attribute, be it passed
>> explicitly as a parameter or the default value, set-default. This issue
>> happens with all autoload functions that use a custom variable: if they
>> are called inside a let form binding that variable and the feature was
>> not loaded yet, the let-binding will have no effect.
>
> To avoid misunderstanding. I was testing with Emacs-26.3 (Ubuntu-20.04
> focal LTS system package) and did not explicitly set lexical binding
> cookie in an .el file. However defcustom autoloading was assumed.
>
> ;; simulate effect of ;;;###autoload
> (defvar org-capture-templates nil)
>
> (defun print-org-capture-templates ()
>   (message "print-org-capture-templates")
>   (pp org-capture-templates)
>   (message "-----"))
> (let ((org-capture-templates
>        '(("d" "default" entry
> 	  (file "/tmp/capture-test.org")
> 	  "* %?"))))
>   (print-org-capture-templates)
>   (require 'org-capture)
>   (print-org-capture-templates))
>
> Second call of print-org-capture templates prints nil with original
> definition of `org-capture-templates' but it prints locally let-bound
> value if I comment out the :set attribute.
>
> I am not disputing any observation from your thorough study
> mid:PAXPR06MB7760A3031924BA897FD082E4C60F9@PAXPR06MB7760.eurprd06.prod.outlook.com
> (it seems message delivery took several hours, so I noticed it after I
> sent my message).

Yes, I was wrong about that. Instead of testing it without :set
argument, I had tested it with a :set argument that was just
set-default plus some messages for debugging. I assumed that it was
equivalent since the documentation says that set-default is the default
value for :set. However it turns out that the actual default value that
is used when no argument is passed is set-default-toplevel-value. With
the later it works (with dynamic binding or autoload variable), but with
the former it doesn't. I think I tested once without :set argument, but
I must have used lexical binding so it didn't work anyway, so I
concluded that it didn't work either in that case.