One of my friends wrote color-identifiers-mode for Emacs[1], which does just that. It supports a bunch of languages and seems reasonably popular. [1]: https://

One of my friends wrote color-identifiers-mode for Emacs[1], which does just that. It supports a bunch of languages and seems reasonably popular. [1]: https://github.com/ankurdave/color-identifiers-mode https://github.com/ankurdave/color-identifiers-mode