lisp/progmodes/cap-words.el

   1 ;;; cap-words.el --- minor mode for motion in CapitalizedWordIdentifiers
   2
   3 ;; Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   4 ;;   Free Software Foundation, Inc.
   5
   6 ;; Author: Dave Love <fx@gnu.org>
   7 ;; Keywords: languages
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Provides Capitalized Words minor mode for word movement in
  27 ;; identifiers CapitalizedLikeThis.
  28
  29 ;; Note that the same effect could be obtained by frobbing the
  30 ;; category of upper case characters to produce word boundaries, but
  31 ;; the necessary processing isn't done for ASCII characters.
  32
  33 ;; Fixme: This doesn't work properly for mouse double clicks.
  34
  35 ;;; Code:
  36
  37 (defun capitalized-find-word-boundary (pos limit)
  38   "Function for use in `find-word-boundary-function-table'.
  39 Looks for word boundaries before capitals."
  40   (save-excursion
  41     (goto-char pos)
  42     (let (case-fold-search)
  43       (if (<= pos limit)
  44           ;; Fixme: Are these regexps the best?
  45           (or (and (re-search-forward "\\=.\\w*[[:upper:]]"
  46                                       limit t)
  47                    (progn (backward-char)
  48                           t))
  49               (re-search-forward "\\>" limit t))
  50         (or (re-search-backward "[[:upper:]]\\w*\\=" limit t)
  51             (re-search-backward "\\<" limit t))))
  52     (point)))
  53
  54
  55 (defconst capitalized-find-word-boundary-function-table
  56   (let ((tab (make-char-table nil)))
  57     (set-char-table-range tab t #'capitalized-find-word-boundary)
  58     tab)
  59   "Assigned to `find-word-boundary-function-table' in Capitalized Words mode.")
  60
  61 ;;;###autoload
  62 (define-minor-mode capitalized-words-mode
  63   "Toggle Capitalized Words mode.
  64
  65 In this minor mode, a word boundary occurs immediately before an
  66 uppercase letter in a symbol.  This is in addition to all the normal
  67 boundaries given by the syntax and category tables.  There is no
  68 restriction to ASCII.
  69
  70 E.g. the beginning of words in the following identifier are as marked:
  71
  72   capitalizedWorDD
  73   ^          ^  ^^
  74
  75 Note that these word boundaries only apply for word motion and
  76 marking commands such as \\[forward-word].  This mode does not affect word
  77 boundaries found by regexp matching (`\\>', `\\w' &c).
  78
  79 This style of identifiers is common in environments like Java ones,
  80 where underscores aren't trendy enough.  Capitalization rules are
  81 sometimes part of the language, e.g. Haskell, which may thus encourage
  82 such a style.  It is appropriate to add `capitalized-words-mode' to
  83 the mode hook for programming language modes in which you encounter
  84 variables like this, e.g. `java-mode-hook'.  It's unlikely to cause
  85 trouble if such identifiers aren't used.
  86
  87 See also `glasses-mode' and `studlify-word'.
  88 Obsoletes `c-forward-into-nomenclature'."
  89   nil " Caps" nil :group 'programming
  90   (set (make-local-variable 'find-word-boundary-function-table)
  91        capitalized-find-word-boundary-function-table))
  92
  93 (provide 'cap-words)
  94
  95 ;; arch-tag: 46513b64-fe5a-4c0b-902c-ed235c22975f
  96 ;;; cap-words.el ends here