Is there a best practice around lazily loading modes when encountering a relevant file extension?
At this point I have roughly 25 different Emacs modes installed, and startup has become slow. For example, although it's great to have clojure-mode at the ready, I rarely use it, and I want to avoid loading it at all unless I open a file with extension .clj. Such a "lazy require" functionality seems like the right way do mode configuration in general..
I found nothing online, so I've taken a crack at it myself.
Instead of:
(require 'clojure-mode)
(require 'tpl-mode)
I have this:
(defun lazy-require (ext mode)
(add-hook
'find-file-hook
`(lambda ()
(when (and (stringp buffer-file-name)
(string-match (concat "\\." ,ext "\\'") buffer-file-name))
(require (quote ,mode))
(,mode)))))
(lazy-require "soy" 'soy-mode)
(lazy-require "tpl" 'tpl-mode)
This seems to work (I'm an elisp newbie so comments are welcome!), but I'm unnerved about finding nothing written about this topic online. Is this a reasonable approach?
The facility you want is called autoloading. The clojure-mode
source file, clojure-mode.el, includes a comment for how to arrange this:
;; Add these lines to your .emacs: ;; (autoload 'clojure-mode "clojure-mode" "A major mode for Clojure" t) ;; (add-to-list 'auto-mode-alist '("\\.clj$" . clojure-mode))
This is one way,
(provide 'my-slime)
(eval-after-load "slime"
'(progn
(setq slime-lisp-implementations
'((sbcl ("/usr/bin/sbcl"))
(clisp ("/usr/bin/clisp")))
common-lisp-hyperspec-root "/home/sujoy/documents/hyperspec/")
(slime-setup '(slime-asdf
slime-autodoc
slime-editing-commands
slime-fancy-inspector
slime-fontifying-fu
slime-fuzzy
slime-indentation
slime-mdot-fu
slime-package-fu
slime-references
slime-repl
slime-sbcl-exts
slime-scratch
slime-xref-browser))
(slime-autodoc-mode)
(setq slime-complete-symbol*-fancy t)
(setq slime-complete-symbol-function 'slime-fuzzy-complete-symbol)
(add-hook 'lisp-mode-hook (lambda () (slime-mode t)))))
(require 'slime)
along with,
;; slime mode
(autoload 'slime "my-slime" "Slime mode." t)
(autoload 'slime-connect "my-slime" "Slime mode." t)
来源:https://stackoverflow.com/questions/6935908/emacs-best-practice-for-lazy-loading-modes-in-emacs