Re: [Emacs-diffs] master 29d1c72: Introduce new value t for compilation-context-lines to eliminate scrolling

[Stefan Monnier]

Hi Alan,

I have a few questions abut your change.

>     * lisp/progmodes/compile.el (compilation-context-lines): Add the new 
> value t.
>     (compilation-set-window): Amend to handle compilation-context-lines being 
> t.
>     (overlay-arrow-overlay): New variable holding an overlay with 
> before-string
>     property "=>".

1- Why `overlay-arrow-overlay` without a `compilation-` prefix?
2- Why insert a prefix string (an "inserted arrow") instead of using
   a "regular overwriting arrow"?
3- Why link the choice of inserted-arrow vs regular-overwriting-arrow to
   compilation-context-lines specifically?


-- Stefan "maybe part of my confusion is that I'm not sufficiently
           familiar with the behavior when there's no left-fringe"