| 1 | ;;; -*-lisp-*- |
| 2 | ;;; |
| 3 | ;;; Basic scanner interface |
| 4 | ;;; |
| 5 | ;;; (c) 2009 Straylight/Edgeware |
| 6 | ;;; |
| 7 | |
| 8 | ;;;----- Licensing notice --------------------------------------------------- |
| 9 | ;;; |
| 10 | ;;; This file is part of the Sensble Object Design, an object system for C. |
| 11 | ;;; |
| 12 | ;;; SOD is free software; you can redistribute it and/or modify |
| 13 | ;;; it under the terms of the GNU General Public License as published by |
| 14 | ;;; the Free Software Foundation; either version 2 of the License, or |
| 15 | ;;; (at your option) any later version. |
| 16 | ;;; |
| 17 | ;;; SOD is distributed in the hope that it will be useful, |
| 18 | ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | ;;; GNU General Public License for more details. |
| 21 | ;;; |
| 22 | ;;; You should have received a copy of the GNU General Public License |
| 23 | ;;; along with SOD; if not, write to the Free Software Foundation, |
| 24 | ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 25 | |
| 26 | (cl:in-package #:sod-parser) |
| 27 | |
| 28 | ;;;-------------------------------------------------------------------------- |
| 29 | ;;; Common scanner implementation.. |
| 30 | |
| 31 | (defmethod file-location ((scanner character-scanner)) |
| 32 | (scanner-file-location scanner)) |
| 33 | |
| 34 | (defmethod file-location ((scanner token-scanner)) |
| 35 | (scanner-file-location scanner)) |
| 36 | |
| 37 | ;;;-------------------------------------------------------------------------- |
| 38 | ;;; Streams on character scanners. |
| 39 | |
| 40 | (defmethod stream-read-char ((stream character-scanner-stream)) |
| 41 | (with-slots (scanner) stream |
| 42 | (if (scanner-at-eof-p scanner) |
| 43 | :eof |
| 44 | (prog1 (scanner-current-char scanner) |
| 45 | (scanner-step scanner))))) |
| 46 | |
| 47 | (defmethod stream-unread-char ((stream character-scanner-stream) char) |
| 48 | (with-slots (scanner) stream |
| 49 | (scanner-unread scanner char))) |
| 50 | |
| 51 | (defmethod stream-peek-char ((stream character-scanner-stream)) |
| 52 | (with-slots (scanner) stream |
| 53 | (scanner-current-char scanner))) |
| 54 | |
| 55 | ;;;-------------------------------------------------------------------------- |
| 56 | ;;; String scanner. |
| 57 | |
| 58 | ;; This is much more convenient for testing lexers than the full character |
| 59 | ;; buffer scanner. |
| 60 | |
| 61 | (export '(string-scanner make-string-scanner string-scanner-p)) |
| 62 | (defstruct (string-scanner |
| 63 | (:constructor make-string-scanner |
| 64 | (string &key (start 0) end |
| 65 | &aux (%string string) |
| 66 | (index start) |
| 67 | (limit (or end (length string)))))) |
| 68 | "Scanner structure for a simple string scanner." |
| 69 | (%string "" :type string :read-only t) |
| 70 | (index 0 :type (and fixnum unsigned-byte)) |
| 71 | (limit nil :type (and fixnum unsigned-byte) :read-only t)) |
| 72 | (define-access-wrapper string-scanner-string string-scanner-%string |
| 73 | :read-only t) |
| 74 | |
| 75 | (defmethod scanner-at-eof-p ((scanner string-scanner)) |
| 76 | (>= (string-scanner-index scanner) (string-scanner-limit scanner))) |
| 77 | |
| 78 | (defmethod scanner-current-char ((scanner string-scanner)) |
| 79 | (char (string-scanner-string scanner) (string-scanner-index scanner))) |
| 80 | |
| 81 | (defmethod scanner-step ((scanner string-scanner)) |
| 82 | (incf (string-scanner-index scanner))) |
| 83 | |
| 84 | (defmethod scanner-capture-place ((scanner string-scanner)) |
| 85 | (string-scanner-index scanner)) |
| 86 | |
| 87 | (defmethod scanner-restore-place ((scanner string-scanner) place) |
| 88 | (setf (string-scanner-index scanner) place)) |
| 89 | |
| 90 | (defmethod scanner-interval |
| 91 | ((scanner string-scanner) place-a &optional place-b) |
| 92 | (with-slots ((string %string) index) scanner |
| 93 | (subseq string place-a (or place-b index)))) |
| 94 | |
| 95 | ;;;-------------------------------------------------------------------------- |
| 96 | ;;; List scanner. |
| 97 | |
| 98 | (export 'list-scanner) |
| 99 | (defstruct (list-scanner |
| 100 | (:constructor make-list-scanner (list &aux (%list list)))) |
| 101 | "Simple token scanner for lists. |
| 102 | |
| 103 | The list elements are the token semantic values; the token types are the |
| 104 | names of the elements' classes. This is just about adequate for testing |
| 105 | purposes, but is far from ideal for real use." |
| 106 | (%list nil :type list)) |
| 107 | (define-access-wrapper list-scanner-list list-scanner-%list) |
| 108 | |
| 109 | (defmethod scanner-step ((scanner list-scanner)) |
| 110 | (pop (list-scanner-list scanner))) |
| 111 | |
| 112 | (defmethod scanner-at-eof-p ((scanner list-scanner)) |
| 113 | (null (list-scanner-list scanner))) |
| 114 | |
| 115 | (defmethod token-type ((scanner list-scanner)) |
| 116 | (class-name (class-of (car (list-scanner-list scanner))))) |
| 117 | |
| 118 | (defmethod token-value ((scanner list-scanner)) |
| 119 | (car (list-scanner-list scanner))) |
| 120 | |
| 121 | (defmethod scanner-capture-place ((scanner list-scanner)) |
| 122 | (list-scanner-list scanner)) |
| 123 | |
| 124 | (defmethod scanner-restore-place ((scanner list-scanner) place) |
| 125 | (setf (list-scanner-list scanner) place)) |
| 126 | |
| 127 | ;;;----- That's all, folks -------------------------------------------------- |