Re: prettify-symbols-mode, derived modes, and compose-region

[Stefan Monnier <monnier@iro.umontreal.ca>]

> problem.  The compose-region solution to this is simply to compose each
> character with a wide enough space, so the user simply has to use
> "\N{EM SPACE}<character>" instead of ?<character> in the alist.
> compose-region will then just superimpose the two and you get a "padded"
> character.  It is very much possible that :align-to could fix this as
> well, judging from the documentation it does sound like it can reproduce
> this feature easily.

You should definitely try, but I suspect it's not going to work
well: :align-to wants to get an "absolute" position of the position
where the flexible space ends whereas in your case you only know how
wide "char + space" should be, but you don't know at which absolute
column "char" will happen to be displayed, so you can't know to which
column to :align-to.


        Stefan