RE: which one to use: custom-set-variables, customize-set-variable, or customize-set-value?

[Drew Adams]

> d> And no, you do not ever need to "check each variable documentation to
> d> see the right way to set its value".  (And you should anyway not rely
> d> on a variable's documentation for that.)
> 
> How's it that possible? How can then I know when to use `setq',
> `setq-default' or `customize-set-variable'?

> t> I think Lele has a point here. Imagine some "simple" variable which
> t> becomes later (i.e. in a later Emacs version) a user option. The
> t> once "right" code in the Emacs init file becomes kind-of "wrong".
> 
> Yes, exactly. Or a buffer-local setting, when it would be even more
> "wrong".

Perhaps I misunderstood.  I thought you meant check the doc for a
description of what the :set function does, initialization, etc.

Anyway, what I meant is to not check _only the documentation_.
Check also the definition of the variable.

While the documentation should correctly report whether it is
an option, and whether it might have a buffer-local value, it
is still good, IMO, to check the defvar/defcustom.

As I said, you can certainly do as you suggest.  My suggestion is
to clearly show in your init file how you are setting the value.
Including for different Emacs versions - so you are aware of such
changes when you read your code later.  But it's just a suggestion.