Re: doc elisp intro cross reference fixes

[Kevin Rodgers]

Stefan Monnier wrote:

> > I disagree.  It is a useful distinction, and programmers can take
> > advantage of it to prevent users from setting variables in a way that
> > they shouldn't (and thence submitting bug reports when they don't get
> > the desired effect).
>
> Can you give concrete examples where the distinction makes sense ?


The example from the "Variable Definitions" node of the Emacs Lisp manual

(cited by Luc): global-font-lock-mode


> > I don't find the explanation of Variable Definitions in the Emacs Lisp
> > manual that Luc cited to be too subtle.
>
> How many elisp programmers know about it and understand it ?


How would I know either thing about other programmers?  But ignorance of

the law is no defense.


> > set-variable and customize are independent mechanisms that are enabled
> > by a doc string convention and the custom-* symbol properties
> > respectively, and as a programmer I'd like to retain control over those
> > mechanisms.
>
> Why should they be independent mechanisms ?
> What is the benefit ?  Why should something be only allowed via M-x
> customize-variable but not via M-x set-variable (and vice-versa, BTW) ?


They are independent because customize was introduced as a new mechanism,
instead of extending set-variable.  Whether they remain so is apparently
up for discussion.  (Would you feel comfortable removing set-variable, or
aliasing it to customize?)

Personally, I only use set-variable and avoid customize completely.  I
understand that programmers (including myself) want to provide the
customize interface to the features they provide.  But if I (as a user)
have to use customize to enable feature foo, I'd rather just do M-x
turn-on-foo-mode; and I don't want to be allowed to set-variable
foo-mode if it doesn't do the right thing.


> As a programmer, the distinction seems very faint and I have a hard time
> coming up with cases where it could make sense to prevent one use
> and allow the other.
>
> As a user it just makes for inconsistency where some variables can be set
> via M-x set-variable while others need M-x customize-variable.


That "inconsistency" accurately reflects the difference between variables
whose values (alone) determine Emacs' behavior and those that don't (because
they interact with other things).

--
Kevin Rodgers