Learn how to setup conditional highlighting for Emacs by writing emacs-lisp to highlight $FlowFixMe
I've been working with Flow a lot since joining Webflow and one of the things that I constantly miss is the
// $FlowFixMe comments. I decided to highlight
// $FlowFixMe comments in red so they stood out.
Emacs makes it trivial to add configuration to highlight specific lines based on certain criteria. In
init.el or any file that you load configuration through, you can add the following:
(defface flow-fix-me-comment '((t (:foreground "#ff0000"))) "Red") (font-lock-add-keywords 'js-mode '(("// $FlowFixMe" 0 'flow-fix-me-comment t)))
Breaking it down:
deffaceallows us to declare a customizable
FACE(you can think of
FACEas a style). We're naming it
font-lock-add-keywordsallows us to highlight a mode based on a specific keyword.
'js-modeis the mode we want to highlight on.
"// $FlowFixMe"is the term we want to use as the criteria for highlighting.
- If the term matches the line, apply the
Make sure to
eval-buffer on the snippet, reload your config or restart Emacs to see the changes take place.
The end result will look like this:
$FlowFixMe comments during development!