Question

For example, I have the file model/user.py open and I want to have a shortcut that opens controller/user.py. Or I want to switch to test/model/testUser.py (contrived example)

I’d like to make an emacs shortcut which given a file currently open, opens files related in various ways.

Answer 1

If the “related files” follow some kind of pattern, I think it’s trivial to write some elisp functions to do the task. Let’s say you have a model and need to open his associated controller, you will need to do something like this:

(defun my-open-related-controller ()
  (interactive)
  (let* ((name (buffer-file-name))) ;gets the filename of the current buffer
    ;; Of course, this is only an example. The point here is that you need
    ;; to "discover" the name of the related file based on the current one.
    (setf name (replace-regexp-in-string "model" "controller" name))

    ;; Now you will open the file(if it isn't open already) and switch to it
    (find-file name)))

Then you can bind the function to, say, F5:

(define-key name-of-the-mode-map [f5] 'my-open-related-controller)

If you want to crate this binding globally, use:

(global-set-key [f5] 'my-open-related-controller)

Of course, this is just a crude example(since you didn’t give many specific details), but should be enough to get you started. Hope it helps!