code.delx.au - gnu-emacs-elpa/blob - packages/ada-mode/ada-wisi-opentoken.el

   1 ;; ada-wisi-opentoken.el --- An indentation function for ada-wisi that indents  -*- lexical-binding:t -*-
   2 ;; OpenTokengrammar statements nicely.
   3
   4 ;; Copyright (C) 2013-2015  Free Software Foundation, Inc.
   5
   6 ;; This file is part of GNU Emacs.
   7
   8 ;; GNU Emacs is free software: you can redistribute it and/or modify
   9 ;; it under the terms of the GNU General Public License as published by
  10 ;; the Free Software Foundation, either version 3 of the License, or
  11 ;; (at your option) any later version.
  12
  13 ;; GNU Emacs is distributed in the hope that it will be useful,
  14 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 ;; GNU General Public License for more details.
  17
  18 ;; You should have received a copy of the GNU General Public License
  19 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  20
  21
  22 ;;; Commentary:
  23
  24 ;; This is an example of a user-added indentation rule.
  25 ;;
  26 ;; In each file that declares OpenToken grammars, enable
  27 ;; ada-indent-opentoken minor mode by adding this near the end of the
  28 ;; file:
  29 ;;
  30 ;; Local Variables:
  31 ;; eval: (ada-indent-opentoken-mode)
  32 ;; End:
  33
  34 ;;; Code:
  35
  36 (require 'ada-mode)
  37 (require 'wisi)
  38
  39 (defun ada-wisi-opentoken ()
  40   "Return appropriate indentation (an integer column) for continuation lines in an OpenToken grammar statement."
  41   ;; We don't do any checking to see if we actually are in an
  42   ;; OpenToken grammar statement, since this rule should only be
  43   ;; included in package specs that exist solely to define OpenToken
  44   ;; grammar fragments.
  45   (save-excursion
  46     (let ((token-text (wisi-token-text (wisi-backward-token))))
  47       (cond
  48        ((equal token-text "<=")
  49         (back-to-indentation)
  50         (+ (current-column) ada-indent-broken))
  51
  52        ((member token-text '("+" "&"))
  53         (while (not (equal "<=" (wisi-token-text (wisi-backward-token)))))
  54         (back-to-indentation)
  55         (+ (current-column) ada-indent-broken))
  56        ))))
  57
  58 (defconst ada-wisi-opentoken-align
  59   "Align rule for OpenToken grammar definitions."
  60   '(ada-opentoken
  61     (regexp  . "[^=]\\(\\s-*\\)<=")
  62     (valid   . (lambda() (not (ada-in-comment-p))))
  63     (modes   . '(ada-mode))))
  64
  65 ;;;###autoload
  66 (define-minor-mode ada-indent-opentoken-mode
  67   "Minor mode for indenting grammar definitions for the OpenToken package.
  68 Enable mode if ARG is positive"
  69   :initial-value t
  70   :lighter       "OpenToken"   ;; mode line
  71
  72   (if ada-indent-opentoken-mode
  73       (progn
  74         ;; This must be after ada-wisi-setup on ada-mode-hook, because
  75         ;; ada-wisi-setup resets wisi-indent-calculate-functions
  76         (add-to-list 'ada-align-rules ada-wisi-opentoken-align)
  77         (add-to-list 'wisi-indent-calculate-functions 'ada-wisi-opentoken))
  78
  79     (setq ada-align-rules (delete ada-wisi-opentoken-align ada-align-rules))
  80     (setq wisi-indent-calculate-functions (delete 'ada-wisi-opentoken wisi-indent-calculate-functions))
  81     ))
  82
  83 (provide 'ada-wisi-opentoken)
  84 ;; end of file