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✼	11/16/2015 - Emacs: How to have tabbing and indentation similar to a more typical text editor (Emacs Lisp)

Emacs: How to have tabbing and indentation similar to a more typical text editor

Monday, November 16th, 2015
05:34:36 GMT

The Emacs editor has a bunch of default behaviors that were driving me crazy:

The built-in automatic indentation
Inserting spaces instead of tabs
Seeming to convert tabs into spaces when you press backspace to try to delete a tab
And frequently just ignoring the tab key instead of just inserting a darn tab, darn it.

(Plus other, less insanity-inducing problems - but those aren't solved in this post.)

And also the automatic indentation in php-mode.

Finally, I figured out how to fix all of that, and make Emacs' tabbing and auto-indenting be more like a typical text editor.

But, I'm pretty new to Emacs, so, there might be side effects or other problems with the below solution I'm not yet aware of. Comments are welcome!

Thanks to everyone on the web who posted useful info and/or code which enabled me to cobble together my current favorite solution.

The only Emacs add-on the below code requires is regtab.el, which makes it possible to indent either one line or entire highlighted regions by pressing tab, and un-indent them by pressing shift-tab.

I put the below code in my ".emacs" settings file. I'm using Emacs 24.5.1.

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
;
; Remove Electric Indent Mode
;

(when (fboundp 'electric-indent-mode) (electric-indent-mode -1))
; 21:16 11/06/2015.  This gets rid of the horrible automatic deletion
; of whitespace.  18:00 11/15/2015.  Among other probably annoying things.
	
(add-hook 'after-change-major-mode-hook (lambda() (electric-indent-mode -1)))

(setq-default c-electric-flag nil)



;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
;
; Apollia's Settings for Making Enter Do Some Nice Autoindenting
;

(defcustom apollia-var--preferred-tab-width 7
	"Only changes the appearance of tabs' length, not their actual length."
)


(defun apollia-func--AutoIndenting-Enter()
	"Inserts a newline, then indents the new line just like the previous line."
	(interactive)
	(newline)
	(
		unless (looking-back "^\n")
		(indent-relative-maybe)
		
	; 18:35 11/15/2015.  This "unless" has to be there because otherwise,
	; this would sometimes mistakenly indent the next line, if the line 
	; you started at had nothing on it but a newline character.
	)
)


(defun apollia-func--Setup-for-AutoIndent()
	"Should be run by the hook after-change-major-mode-hook, to hopefully fix the settings after a major mode change ruins them."
	
	(local-set-key "\r" 'apollia-func--AutoIndenting-Enter )
	(global-set-key "\r" 'apollia-func--AutoIndenting-Enter)
	(setq-default indent-tabs-mode t)
	(setq-default tab-width apollia-var--preferred-tab-width )
	(global-set-key [backspace] 'backward-delete-char)
)

(add-hook 'after-change-major-mode-hook 'apollia-func--Setup-for-AutoIndent)

(apollia-func--Setup-for-AutoIndent)


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; Add-on:	regtab
;	http://github.com/zorgnaz/regtab
;
;

(require 'regtab)

;(define-minor-mode regtab-mode "Regular Tabs Minor Mode" :lighter nil :keymap regtab-mode-map)

(add-hook 'after-change-major-mode-hook 'regtab-mode)
  
(regtab-mode)

I had some trouble figuring out how to make php-mode stop doing automatic indent. So, finally, I just resorted to the brute force method of editing php-mode.el's source code.

In php-mode.el, I changed every instance of indent-tabs-mode nil to indent-tabs-mode t, and every instance of tab-width 4 to tab-width 7. (But you can use whatever tab-width number you like).

I don't yet know of a less invasive way to fix it than that. But, that worked.

To stop regtab.el from displaying the text "regtab" in your modeline, you can comment out these lines in regtab.el:

(define-minor-mode regtab-mode "Regular Tabs Minor Mode"
  :lighter " regtab" :keymap regtab-mode-map)

And use this line instead, with "lighter" set to "nil". (It's included in the box of code above, so you can just uncomment it.)

(define-minor-mode regtab-mode "Regular Tabs Minor Mode" :lighter nil :keymap regtab-mode-map)

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Emacs: How to have tabbing and indentation similar to a more typical text editor
11/16/2015

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Emacs: How to have tabbing and indentation similar to a more typical text editor11/16/2015

Emacs: How to have tabbing and indentation similar to a more typical text editor
11/16/2015