lisp/nxml/nxml-util.el

   1 ;;; nxml-util.el --- utility functions for nxml-*.el  -*- lexical-binding:t -*-
   2
   3 ;; Copyright (C) 2003, 2007-2017 Free Software Foundation, Inc.
   4
   5 ;; Author: James Clark
   6 ;; Keywords: wp, hypermedia, languages, XML
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;;; Code:
  26
  27 (defconst nxml-debug nil
  28   "Enable nxml debugging.  Effective only at compile time.")
  29
  30 (defsubst nxml-debug (format &rest args)
  31   (when nxml-debug
  32     (apply #'message format args)))
  33
  34 (defmacro nxml-debug-change (name start end)
  35   (when nxml-debug
  36     `(nxml-debug "%s: %S" ,name
  37                 (buffer-substring-no-properties ,start ,end))))
  38
  39 (defun nxml-make-namespace (str)
  40   "Return a symbol for the namespace URI STR.
  41 STR must be a string.  If STR is the empty string, return nil.
  42 Otherwise, return the symbol whose name is STR prefixed with a colon."
  43   (if (string-equal str "")
  44       nil
  45     (intern (concat ":" str))))
  46
  47 (defun nxml-namespace-name (ns)
  48   "Return the namespace URI corresponding to the symbol NS.
  49 This is the inverse of `nxml-make-namespace'."
  50   (and ns (substring (symbol-name ns) 1)))
  51
  52 (defconst nxml-xml-namespace-uri
  53   (nxml-make-namespace "http://www.w3.org/XML/1998/namespace"))
  54
  55 (defconst nxml-xmlns-namespace-uri
  56   (nxml-make-namespace "http://www.w3.org/2000/xmlns/"))
  57
  58 (defmacro nxml-with-degradation-on-error (context &rest body)
  59   (declare (indent 1) (debug t))
  60   (if (not nxml-debug)
  61       (let ((error-symbol (make-symbol "err")))
  62         `(condition-case ,error-symbol
  63              (progn ,@body)
  64            (error
  65             (nxml-degrade ,context ,error-symbol))))
  66     `(progn ,@body)))
  67
  68 (defmacro nxml-with-invisible-motion (&rest body)
  69   "Evaluate body without calling any point motion hooks."
  70   (declare (indent 0) (debug t))
  71   `(let ((inhibit-point-motion-hooks t))
  72      ,@body))
  73
  74 (defun nxml-display-file-parse-error (err)
  75   (let* ((filename (nth 1 err))
  76          (buffer (find-file-noselect filename))
  77          (pos (nth 2 err))
  78          (message (nth 3 err)))
  79     (pop-to-buffer buffer)
  80     ;; What's the right thing to do if the buffer's modified?
  81     ;; The position in the saved file could be completely different.
  82     (goto-char (if (buffer-modified-p) 1 pos))
  83     (error "%s" message)))
  84
  85 (defun nxml-signal-file-parse-error (file pos message &optional error-symbol)
  86   (signal (or error-symbol 'nxml-file-parse-error)
  87           (list file pos message)))
  88
  89 (define-error 'nxml-error nil)
  90 (define-error 'nxml-file-parse-error "Error parsing file" 'nxml-error)
  91
  92 (provide 'nxml-util)
  93
  94 ;;; nxml-util.el ends here