Re: turn-on/off-*MODE*

[Stefan Monnier]

> Is there a general guideline for when to add or not add these?

Yes: never add them.

> + ;;;###autoload
> + (defun turn-on-hl-line ()
> +   "Unconditionally turn on highlight-line mode."
> +   (hl-line-mode 1))

(hl-line-mode) is the same as (hl-line-mode 1), so you can rewrite is as:

   ;;;###autoload
   (defun turn-on-hl-line ()
     "Unconditionally turn on highlight-line mode."
     (hl-line-mode))
=>

   ;;;###autoload
   (defalias 'turn-on-hl-line #'hl-line-mode
     "Unconditionally turn on highlight-line mode.")

at which point you can decide it's not worth the trouble.

> + ;;;###autoload
> + (defun turn-off-hl-line ()
> +   "Unconditionally turn off highlight-line mode."
> +   (hl-line-mode -1))

I've virtually never seen it used.  So for the very rare cases
(lambda () (foo-mode -1)) works just as well and isn't that much longer
#'turn-off-foo-mode.


        Stefan