[nongnu] elpa/cdlatex b27b1bb79a 10/13: Integrate cdlatex-electricindex-mode

[ELPA Syncer]

branch: elpa/cdlatex
commit b27b1bb79ab4f0e7c112772c132d5406cd908bee
Author: Carsten Dominik <dominik@carstens-mbp.speedport.ip>
Commit: Carsten Dominik <dominik@carstens-mbp.speedport.ip>

    Integrate cdlatex-electricindex-mode
---
 cdlatex.el | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)

diff --git a/cdlatex.el b/cdlatex.el
index a6a36c2fe1..f62f0f52bc 100644
--- a/cdlatex.el
+++ b/cdlatex.el
@@ -2250,6 +2250,95 @@ and after changes to these variables via
   (if (string-match "\\?" string)
       (cdlatex-position-cursor)))
 
+;;; cdlatex-electric-index-mode
+
+(defgroup cdlatex-electricindex nil
+  "LaTeX electric digit indices."
+  :tag "cdlatex-electricindex"
+  :link '(url-link :tag "Home Page" "https://github.com/cdominik/cdlatex";)
+  :prefix "cdlatex-electricindex-"
+  :group 'tex)
+
+(defvar cdlatex-electricindex-mode nil
+  "Determines if cdlatex-electricindex minor mode is active.")
+(make-variable-buffer-local 'cdlatex-electricindex-mode)
+
+(defvar cdlatex-electricindex-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map  "1"        #'cdlatex-electricindex-digit)
+    (define-key map  "2"        #'cdlatex-electricindex-digit)
+    (define-key map  "3"        #'cdlatex-electricindex-digit)
+    (define-key map  "4"        #'cdlatex-electricindex-digit)
+    (define-key map  "5"        #'cdlatex-electricindex-digit)
+    (define-key map  "6"        #'cdlatex-electricindex-digit)
+    (define-key map  "7"        #'cdlatex-electricindex-digit)
+    (define-key map  "8"        #'cdlatex-electricindex-digit)
+    (define-key map  "9"        #'cdlatex-electricindex-digit)
+    (define-key map  "0"        #'cdlatex-electricindex-digit)
+    map)
+  "Keymap for cdlatex-electricindex minor mode.")
+
+;;;###autoload
+(defun turn-on-cdlatex-electricindex ()
+  "Turn on cdlatex-electricindex minor mode."
+  (cdlatex-electricindex-mode t))
+
+;;;###autoload
+(define-minor-mode cdlatex-electricindex-mode
+  "Minor mode for electric insertion of numbered indixes.
+
+cdlatex-electricindex is a minor mode supporting fast digit index
+insertation in LaTeX math. For example typing x 1 2 will insert
+x_{12}.
+
+To turn cdlatex-electricindex Minor Mode on and off in a
+particular buffer, use `M-x cdlatex-electricindex-mode'.
+
+To turn on cdlatex-electricindex Minor Mode for all LaTeX files,
+add one of the following lines to your .emacs file:
+
+    (add-hook 'latex-mode-hook #'turn-on-cdlatex-electricindex)
+
+This index insertion will only work when the cursor is in a LaTeX
+math environment, based on (texmathp). If texmathp is not
+available, math math-mode will be assumed.
+
+Entering `cdlatex-electricindex-mode' calls the hook
+`cdlatex-electricindex-mode-hook'."
+  :lighter " EI")
+
+(defun cdlatex-electricindex-active-here ()
+  (if (eq major-mode 'latex-mode)
+      (if (fboundp 'texmathp)
+          (texmathp)
+        t)
+    t))
+
+(defun cdlatex-electricindex-digit ()
+  "Insert digit, maybe as an index to a quantity in math environment."
+  (interactive)
+  (if (not (cdlatex-electricindex-active-here))
+      (self-insert-command 1)
+    (let ((digit (char-to-string (event-basic-type last-command-event))))
+      (if (looking-back "[a-zA-Z]" (1- (point)))
+          (insert "_" digit " ")
+        (if (looking-back "\\(_[0-9]\\) ?" (- (point) 3))
+            (progn
+              (goto-char (match-beginning 1))
+              (forward-char 1)
+              (insert "{")
+              (forward-char 1)
+              (insert digit "}")
+              (if (looking-at " ")
+                  (forward-char 1)
+                (insert " ")))
+          (if (looking-back "_{\\([0-9]+\\)} ?"
+                            (max (- (point) 10) (point-min)))
+              (save-excursion
+                (goto-char (match-end 1))
+                (insert digit))
+            (self-insert-command 1)))))))
+
 ;;; Menus --------------------------------------------------------------------
 
 ;; Define a menu for the menu bar if Emacs is running under X
@@ -2272,6 +2361,8 @@ and after changes to these variables via
     ["Build Full Customize Menu" cdlatex-create-customize-menu
      (fboundp 'customize-menu-create)])
    "----"
+   ["Toggle electricindex"      cdlatex-electricindex-mode t]
+   "----"
    ["Show documentation"      cdlatex-show-commentary t]
    ["Help with KEYWORD Cmds" cdlatex-command-help t]
    ["Reset CDLaTeX Mode"       cdlatex-reset-mode t]))