Re: [Patch]: Allow overlay arrows to be inserted before the text at column zero rather than splatting it.

[Eli Zaretskii]

> Date: Sun, 18 Aug 2019 18:43:56 +0000
> Cc: address@hidden
> From: Alan Mackenzie <address@hidden>
> 
> I don't think there's anything else in Emacs at the moment that could
> take its place.  The essence here is being able to insert "=>" onto the
> display _without_ disturbing the horizontal alignment

Sorry, I'm confused now: how can you insert the arrow without either
moving the rest of the line to the right or overwriting its first few
glyphs?  Where does the space for the arrow come from?