Buffer-locally overriding minor-mode key bindings in Emacs

Question

I want to use a minor mode which rebinds a major-mode key that I definitely want to keep. How can I rebind the key without deleting it from the minor-mode map globally? I kn

Answer 1

In my case, company-mode was overriding the cider-repl-mode bindings for M-p and M-n when the Company completions menu was showing. The keymap for the completions menu is company-active-map, but there's no minor mode corresponding to it (company-mode is for when the menu is not active), so I couldn't use any of the existing answers.

Here's what I came up with instead:

(add-hook 'cider-repl-mode-hook
          (lambda ()
            (make-local-variable 'company-active-map)
            (setq company-active-map (copy-tree company-active-map))
            (define-key company-active-map (kbd "M-p") nil)
            (define-key company-active-map (kbd "M-n") nil)))