Ligature request : +. *. -. /.

Hello FiraCoders !

I just installed FiraCode on my linux machine and it all works greatly on my spacemacs config

(Well, I did had to add such a code in my init file...)

But while working on ocaml, I realized the float operators :

  a +. b
; a -. b
; a *. b
; a /. b

were not replaced.

I reactivated tuareg's prettify-symbol-mode, to see if it could make things better

but it did not (entirely)
What I get is this:

  a +. b  (* fira's + *)
; a ∸ b (* prettified by tuareg *)
; a *. (* fira's * *)
; a ÷ b (* prettified by tuareg *)

So I would ask for the addition of these operators, ligatured.

As reference, Tuareg's prettify mode makes this mapping :

+. ---> ∔
-. ---> ∸
*. ---> ∙
/. ---> ÷

Though to keep spacing it would be nice to have new ligs, which is what you guys would go for I think.

bonus:
(For now, if anybody has any idea how to make spacemacs bypass fira's + and - to allow tuareg to do his thing?)

The issue names no source file or test. Start by locating Fira Code's existing ligature definitions for + and * and compare their handling of OCaml operators; done means +., -., *., and /. render as the requested ligatures.