add ruby-electric.el

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@8090 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Sun Mar  6 13:04:10 2005  Dee Zsombor  <zsombor@ruby-lang.org>
+
+	* misc/ruby-electric.el: added.
+	* misc/Readme: updated.
+
 Sun Mar  6 11:47:10 2005  Sam Roberts  <sroberts@uniserve.com>
 
 	* lib/pp.rb: rdoced.  [ruby-core:4490]

misc/README

@@ -3,3 +3,4 @@ inf-ruby.el	program to run ruby under emacs
 ruby-mode.el	ruby mode for emacs
 rubydb2x.el	ruby debugger support for emacs 19.2x or before
 rubydb3x.el	ruby debugger support for emacs 19.3x or later
+ruby-electric.el emacs minor mode providing electric commands

misc/ruby-electric.el

@@ -0,0 +1,200 @@
+;; -*-Emacs-Lisp-*-
+;;
+;; ruby-electric.el --- electric editing commands for ruby files
+;;
+;; Copyright (C) 2005 by Dee Zsombor <dee dot zsombor at gmail dot com>.
+;; Released under same license terms as Ruby.
+;;
+;; Due credit: this work was inspired by a code snippet posted by
+;; Frederick Ros at http://rubygarden.org/ruby?EmacsExtensions.
+;;
+;; Following improvements where added:
+;;
+;;       - handling of strings of type 'here document'
+;;       - more keywords, with special handling for 'do'
+;;       - packaged into a minor mode
+;;
+;; Usage:
+;;
+;;    0) copy ruby-electric.el into directory where emacs can find it.
+;;
+;;    1) modify your startup file (.emacs or whatever) by adding
+;;       following line:
+;;
+;;            (require 'ruby-electric)
+;;
+;;       note that you need to have font lock enabled beforehand.
+;;
+;;    2) toggle Ruby Electric Mode on/off with ruby-electric-mode.
+;;
+;; Changelog:
+;;
+;;  2005/Jan/14: inserts matching pair delimiters like {, [, (, ', ",
+;;  ' and | .
+;;
+;;  2005/Jan/14: added basic Custom support for configuring keywords
+;;  with electric closing.
+;;
+;;  2005/Jan/18: more Custom support for configuring characters for
+;;  which matching expansion should occur.
+;;
+;;  2005/Jan/18: no longer uses 'looking-back' or regexp character
+;;  classes like [:space:] since they are not implemented on XEmacs.
+;;
+;;  2005/Feb/01: explicitly provide default argument of 1 to
+;;  'backward-word' as it requires it on Emacs 21.3
+;;
+;;  2005/Mar/06: now stored inside ruby CVS; customize pages now have
+;;  ruby as parent; cosmetic fixes.
+
+
+(require 'ruby-mode)
+
+(defgroup ruby-electric nil
+  "Minor mode providing electric editing commands for ruby files"
+  :group 'ruby) 
+
+(defconst ruby-electric-expandable-do-re
+  "do\\s-$")
+
+(defconst ruby-electric-expandable-bar
+  "\\s-\\(do\\|{\\)\\s-+|")
+
+(defvar ruby-electric-matching-delimeter-alist
+  '((?\[ . ?\])
+    (?\( . ?\))
+    (?\' . ?\')
+    (?\` . ?\`)
+    (?\" . ?\")))
+
+(defcustom ruby-electric-simple-keywords-re 
+  "\\(def\\|if\\|class\\|module\\|unless\\|case\\|while\\|do\\|until\\|for\\|begin\\)"
+  "*Regular expresion matching keywords for which closing 'end'
+is to be inserted."
+  :type 'regexp :group 'ruby-electric)
+
+(defcustom ruby-electric-expand-delimiters-list '(all)
+  "*List of contexts where matching delimiter should be
+inserted. The word 'all' will do all insertions."
+  :type '(set :extra-offset 8
+	      (const :tag "Everything" all )
+	      (const :tag "Curly brace" ?\{ )
+	      (const :tag "Square brace" ?\[ )
+	      (const :tag "Round brace" ?\( )
+	      (const :tag "Quote" ?\' )
+	      (const :tag "Double quote" ?\" )
+	      (const :tag "Back quote" ?\` )
+	      (const :tag "Vertical bar" ?\| ))
+  :group 'ruby-electric) 
+
+(defcustom ruby-electric-newline-before-closing-bracket nil
+  "*Controls whether a newline should be inserted before the
+closing bracket or not."
+  :type 'boolean :group 'ruby-electric)
+
+(define-minor-mode ruby-electric-mode
+  "Toggle Ruby Electric minor mode.
+With no argument, this command toggles the mode.  Non-null prefix
+argument turns on the mode.  Null prefix argument turns off the
+mode.
+
+When Ruby Electric mode is enabled, an indented 'end' is
+heuristicaly inserted whenever typing a word like 'module',
+'class', 'def', 'if', 'unless', 'case', 'until', 'for', 'begin',
+'do'. Simple, double and back quotes as well as braces are paired
+auto-magically. Expansion does not occur inside comments and
+strings. Note that you must have Font Lock enabled."
+  ;; initial value.
+  nil
+  ;;indicator for the mode line.
+  " REl"
+  ;;keymap
+  ruby-mode-map
+  (ruby-electric-setup-keymap))
+
+(defun ruby-electric-setup-keymap()
+  (define-key ruby-mode-map " " 'ruby-electric-space)
+  (define-key ruby-mode-map "{" 'ruby-electric-curlies)
+  (define-key ruby-mode-map "(" 'ruby-electric-matching-char)
+  (define-key ruby-mode-map "[" 'ruby-electric-matching-char)
+  (define-key ruby-mode-map "\"" 'ruby-electric-matching-char)
+  (define-key ruby-mode-map "\'" 'ruby-electric-matching-char)
+  (define-key ruby-mode-map "|" 'ruby-electric-bar))
+
+(defun ruby-electric-space (arg)
+  (interactive "P")
+  (self-insert-command (prefix-numeric-value arg))
+  (if (ruby-electric-space-can-be-expanded-p)
+      (save-excursion
+	(ruby-indent-line t)
+	(newline)
+	(ruby-insert-end))))
+
+(defun ruby-electric-code-at-point-p()
+  (and ruby-electric-mode
+       (let* ((properties (text-properties-at (point))))
+	 (and (null (memq 'font-lock-string-face properties))
+	      (null (memq 'font-lock-comment-face properties))))))
+
+(defun ruby-electric-string-at-point-p()
+  (and ruby-electric-mode
+       (consp (memq 'font-lock-string-face (text-properties-at (point))))))
+
+(defun ruby-electric-is-last-command-char-expandable-punct-p()
+  (or (memq 'all ruby-electric-expand-delimiters-list)
+      (memq last-command-char ruby-electric-expand-delimiters-list))) 
+
+(defun ruby-electric-space-can-be-expanded-p()
+  (if (ruby-electric-code-at-point-p)
+      (let* ((ruby-electric-keywords-re 
+	      (concat ruby-electric-simple-keywords-re "\\s-$"))
+	     (ruby-electric-single-keyword-in-line-re 
+	      (concat "\\s-*" ruby-electric-keywords-re)))
+	(save-excursion
+	  (backward-word 1)
+	  (or (looking-at ruby-electric-expandable-do-re)
+	      (and (looking-at ruby-electric-keywords-re)
+		   (not (string= "do" (match-string 1)))
+		   (progn
+		     (beginning-of-line)
+		     (looking-at ruby-electric-single-keyword-in-line-re))))))))
+
+
+(defun ruby-electric-curlies(arg)
+  (interactive "P")
+  (self-insert-command (prefix-numeric-value arg))
+  (if (ruby-electric-is-last-command-char-expandable-punct-p)
+      (cond ((ruby-electric-code-at-point-p)
+	     (insert " ")
+	     (save-excursion
+	       (if ruby-electric-newline-before-closing-bracket
+		   (newline))
+	       (insert "}")))
+	    ((ruby-electric-string-at-point-p)
+	     (save-excursion
+	       (backward-char 1)
+	       (when (char-equal ?\# (preceding-char))
+		 (forward-char 1)
+		 (insert "}")))))))
+
+(defun ruby-electric-matching-char(arg)
+  (interactive "P")
+  (self-insert-command (prefix-numeric-value arg))
+  (and (ruby-electric-is-last-command-char-expandable-punct-p)
+       (ruby-electric-code-at-point-p)
+       (save-excursion
+	 (insert (cdr (assoc last-command-char 
+			     ruby-electric-matching-delimeter-alist))))))
+
+(defun ruby-electric-bar(arg)
+  (interactive "P")
+  (self-insert-command (prefix-numeric-value arg))
+  (and (ruby-electric-is-last-command-char-expandable-punct-p)
+       (ruby-electric-code-at-point-p)
+       (and (save-excursion (re-search-backward ruby-electric-expandable-bar nil t))
+	    (= (point) (match-end 0))) ;looking-back is missing on XEmacs
+       (save-excursion 
+	 (insert "|"))))
+
+
+(provide 'ruby-electric)