I am trying to get ligatures working in emacs with "Fantasque Sans Mono Nerd Font Mono" (that's its name...)
My script is the following:
(provide 'add-fantasque-ligatures)
(defconst fantasque-fontlock-keywords-alist
(mapcar (lambda (regex-char-pair)
`(,(car regex-char-pair)
(0 (prog1 ()
(compose-region (match-beginning 1)
(match-end 1)
,(concat (list ?\C-i)
(list (decode-char 'ucs (cadr regex-char-pair)))))))))
'(("\\(!=\\)" #xe10a)
("\\(==\\)" #xe103)
("\\(->\\)" #xe112)
("\\(<-\\)" #xe121)
("[^<]\\(<=\\)" #xe11b)
("\\(&&\\)" #xe038)
("[^>]\\(>=\\)" #xe10c))))
(defun add-fantasque-ligatures ()
(font-lock-add-keywords nil fantasque-fontlock-keywords-alist))
(add-hook 'prog-mode-hook
#'add-fantasque-ligatures)
It works fine, except for the &&. Emacs displays a play button in a filled circle. I penta-checked it, and U+e038 is its unicode value.
I have an idea, though, what emacs does here. There are some other ligatures I checked too, like ||, and emacs displayed a play button in an unfilled circle. I changed the font, and the && and || still did not work. I think there are some unicode characters, that emacs overwrites to make them font-independent. Is there a way though to overcome this problem, and display the correct ligatures?
