我已经编写了这个小小模式,以便在主模式执行初始缩进行为后让TAB键继续缩进和/或在主模式认为不需要缩进时强制缩进.
有人向我指出的是,组合setq和make-local-variable大概可以简化为一个let范围.鉴于这需要同时跨多个缓冲区工作,如何使用let而不是make-local-variable？
;;; dwim-tab.el --- minor mode to force indentation when TAB would otherwise stall
; internal tracking variables
(setq dwim-tab-point-before nil)
(setq dwim-tab-point-after nil)
(defun dwim-tab ()
"Indents normally once, then switches to tab-to-tab-stop if invoked again.
Always performs tab-to-tab-stop if the first TAB press does not cause the
point to move."
(interactive)
(setq dwim-tab-point-before (point))
(if (eq dwim-tab-point-before dwim-tab-point-after) ; pressed TAB again
(tab-to-tab-stop)
(indent-for-tab-command))
(if (eq (point) dwim-tab-point-before) ; point didn't move
(tab-to-tab-stop))
(setq dwim-tab-point-after (point)))
(define-minor-mode dwim-tab-mode
"Toggle dwim-tab-mode.
With a non-nil argument, turns on dwim-tab-mode. With a nil argument, turns it
off.
When dwim-tab-mode is enabled, pressing the TAB key once will behave as normal,
but pressing it subsequent times, will continue to indent, using
tab-to-tab-stop.
If dwim-tab determines that the first TAB key press resulted in no movement of
the point, it will indent according to tab-to-tab-stop instead."
:init-value nil
:lighter " DWIM"
:keymap '(("\t" . dwim-tab))
(make-local-variable 'dwim-tab-point-before)
(make-local-variable 'dwim-tab-point-after))
(provide 'dwim-tab)
这样做你想要的吗？看马,没有变数!
(defun tab-dwim ()
(interactive)
(when (or (eq last-command this-command)
(= (point) (progn
(indent-for-tab-command)
(point))))
(tab-to-tab-stop)))
假设indent-for-tab-command不会再次神奇地开始缩进,那么最后一次命令检查并不是绝对必要的.但它的CPU效率略高.