compile-command.el

;; Automatically loads the compile command from a file in the current working directory.
(defun alex/default-compile-command ()
  (interactive)
  (let ((file (expand-file-name ".compile-command" default-directory)))
    (when (file-readable-p file)
      (setq-local compile-command
                  (string-trim
                   (with-temp-buffer
                     (insert-file-contents file)
                     (buffer-string))))
      (message "Command set to: %s" compile-command))))

;; Recompiles if compile-command is set, or else tries to set it to the contents of .compile-command.
(defun alex/recompile ()
  (interactive)
  (when (or (null compile-command)
            (string-empty-p compile-command))
    (alex/default-compile-command))
  (recompile))

(setq-default compile-command nil)

;; Enable compilation-mode keyboard shortcuts.
(keymap-global-set "C-c c" #'compile)
(keymap-global-set "C-c r" #'alex/recompile)