Add autoloads, make code more concise & idiomatic

- Use define-derived-mode to declare nix-mode
- Use autoloads to ensure nix-mode is usable (and enabled) without needing `require`
- Use set + make-local-variable instead of longer 2-step equivalent
This commit is contained in:
Steve Purcell 2014-06-05 11:04:48 +01:00 committed by Eelco Dolstra
parent ee7fe64c0a
commit 61c464f252

View file

@ -1,10 +1,51 @@
;;; nix-mode.el --- Major mode for editing Nix expressions.
;;; nix-mode.el --- Major mode for editing Nix expressions
;; Author: Eelco Dolstra
;; URL: https://github.com/NixOS/nix/tree/master/misc/emacs
;; Version: 1.0
(defun nix-mode ()
;;; Commentary:
;;; Code:
(defconst nix-font-lock-keywords
'("\\<if\\>" "\\<then\\>" "\\<else\\>" "\\<assert\\>" "\\<with\\>"
"\\<let\\>" "\\<in\\>" "\\<rec\\>" "\\<inherit\\>" "\\<or\\>"
("\\<true\\>" . font-lock-builtin-face)
("\\<false\\>" . font-lock-builtin-face)
("\\<null\\>" . font-lock-builtin-face)
("\\<import\\>" . font-lock-builtin-face)
("\\<derivation\\>" . font-lock-builtin-face)
("\\<baseNameOf\\>" . font-lock-builtin-face)
("\\<toString\\>" . font-lock-builtin-face)
("\\<isNull\\>" . font-lock-builtin-face)
("[a-zA-Z][a-zA-Z0-9\\+-\\.]*:[a-zA-Z0-9%/\\?:@&=\\+\\$,_\\.!~\\*'-]+"
. font-lock-constant-face)
("\\<\\([a-zA-Z_][a-zA-Z0-9_'\-\.]*\\)[ \t]*="
(1 font-lock-variable-name-face nil nil))
("<[a-zA-Z0-9._\\+-]+\\(/[a-zA-Z0-9._\\+-]+\\)*>"
. font-lock-constant-face)
("[a-zA-Z0-9._\\+-]*\\(/[a-zA-Z0-9._\\+-]+\\)+"
. font-lock-constant-face))
"Font lock keywords for nix.")
(defvar nix-mode-syntax-table
(let ((table (make-syntax-table)))
(modify-syntax-entry ?/ ". 14" table)
(modify-syntax-entry ?* ". 23" table)
(modify-syntax-entry ?# "< b" table)
(modify-syntax-entry ?\n "> b" table)
table)
"Syntax table for Nix mode.")
(defun nix-indent-line ()
"Indent current line in a Nix expression."
(interactive)
(indent-relative-maybe))
;;;###autoload
(define-derived-mode nix-mode fundamental-mode "Nix"
"Major mode for editing Nix expressions.
The following commands may be useful:
@ -25,93 +66,29 @@ The hook `nix-mode-hook' is run when Nix mode is started.
\\{nix-mode-map}
"
(interactive)
(kill-all-local-variables)
(setq major-mode 'nix-mode)
(setq mode-name "Nix")
(use-local-map nix-mode-map)
(set-syntax-table nix-mode-syntax-table)
;; Font lock support.
(setq font-lock-defaults '(nix-keywords nil nil nil nil))
(setq font-lock-defaults '(nix-font-lock-keywords nil nil nil nil))
;; Automatic indentation [C-j].
(make-local-variable 'indent-line-function)
(setq indent-line-function 'nix-indent-line)
(set (make-local-variable 'indent-line-function) 'nix-indent-line)
;; Indenting of comments.
(make-local-variable 'comment-start)
(setq comment-start "# ")
(make-local-variable 'comment-end)
(setq comment-end "")
(make-local-variable 'comment-start-skip)
(setq comment-start-skip "\\(^\\|\\s-\\);?#+ *")
(set (make-local-variable 'comment-start) "# ")
(set (make-local-variable 'comment-end) "")
(set (make-local-variable 'comment-start-skip) "\\(^\\|\\s-\\);?#+ *")
;; Filling of comments.
(make-local-variable 'adaptive-fill-mode)
(setq adaptive-fill-mode t)
(make-local-variable 'paragraph-start)
(setq paragraph-start "[ \t]*\\(#+[ \t]*\\)?$")
(make-local-variable 'paragraph-separate)
(setq paragraph-separate paragraph-start)
(run-hooks 'nix-mode-hook))
(set (make-local-variable 'adaptive-fill-mode) t)
(set (make-local-variable 'paragraph-start) "[ \t]*\\(#+[ \t]*\\)?$")
(set (make-local-variable 'paragraph-separate) paragraph-start))
(defvar nix-mode-map nil
"Keymap for Nix mode.")
(setq nix-mode-map (make-sparse-keymap))
;(define-key nix-mode-map [tab] 'tab-to-tab-stop)
(defvar nix-keywords
'("\\<if\\>" "\\<then\\>" "\\<else\\>" "\\<assert\\>" "\\<with\\>"
"\\<let\\>" "\\<in\\>" "\\<rec\\>" "\\<inherit\\>" "\\<or\\>"
("\\<true\\>" . font-lock-builtin-face)
("\\<false\\>" . font-lock-builtin-face)
("\\<null\\>" . font-lock-builtin-face)
("\\<import\\>" . font-lock-builtin-face)
("\\<derivation\\>" . font-lock-builtin-face)
("\\<baseNameOf\\>" . font-lock-builtin-face)
("\\<toString\\>" . font-lock-builtin-face)
("\\<isNull\\>" . font-lock-builtin-face)
("[a-zA-Z][a-zA-Z0-9\\+-\\.]*:[a-zA-Z0-9%/\\?:@&=\\+\\$,_\\.!~\\*'-]+"
. font-lock-constant-face)
("\\<\\([a-zA-Z_][a-zA-Z0-9_'\-\.]*\\)[ \t]*="
(1 font-lock-variable-name-face nil nil))
("<[a-zA-Z0-9._\\+-]+\\(/[a-zA-Z0-9._\\+-]+\\)*>"
. font-lock-constant-face)
("[a-zA-Z0-9._\\+-]*\\(/[a-zA-Z0-9._\\+-]+\\)+"
. font-lock-constant-face)))
(defvar nix-mode-syntax-table nil
"Syntax table for Nix mode.")
(if nix-mode-syntax-table
nil
;;;###autoload
(progn
(setq nix-mode-syntax-table (make-syntax-table))
(modify-syntax-entry ?/ ". 14" nix-mode-syntax-table)
(modify-syntax-entry ?* ". 23" nix-mode-syntax-table)
(modify-syntax-entry ?# "< b" nix-mode-syntax-table)
(modify-syntax-entry ?\n "> b" nix-mode-syntax-table)))
(defun nix-indent-line ()
"Indent current line in a Nix expression."
(interactive)
(indent-relative-maybe))
(setq auto-mode-alist (cons '("\\.nix\\'" . nix-mode) auto-mode-alist))
(setq auto-mode-alist (cons '("\\.nix.in\\'" . nix-mode) auto-mode-alist))
(add-to-list 'auto-mode-alist '("\\.nix\\'" . nix-mode))
(add-to-list 'auto-mode-alist '("\\.nix.in\\'" . nix-mode)))
(provide 'nix-mode)