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highlight-numbers

highlight-numbers is an Emacs minor mode that highlights numeric literals in source code.

To turn it on:

M-x highlight-numbers-mode

To turn it on automatically for foo-mode:

(add-hook 'foo-mode-hook 'highlight-numbers-mode)

To turn it on for most programming modes:

(add-hook 'prog-mode-hook 'highlight-numbers-mode)

The face used for highlighting is highlight-numbers-number. By default it inherits from font-lock-constant-face.

Regular expressions used to match the numeric literals are stored in highlight-numbers-modelist.

The package is available in MELPA, so if you have MELPA in package-archives, all you need is

M-x package-install RET highlight-numbers RET

If you don't, open highlight-numbers.el and issue

M-x package-install-from-buffer