* dom.el: New file.

parent 549a1bae
......@@ -8,6 +8,10 @@
Remove spurious reference to symbol category_properties.
* progmodes/cc-engine.el (c-state-pp-to-literal): Fix here.
2014-11-26 Lars Magne Ingebrigtsen <larsi@gnus.org>
* dom.el: New file.
2014-11-26 Glenn Morris <rgm@gnu.org>
* arc-mode.el (archive-visit-single-files): Add :version.
......
;;; dom.el --- XML/HTML (etc.) DOM manipulation and searching functions
;; Copyright (C) 2014 Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
;; Keywords: xml, html
;; This file is part of GNU Emacs.
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;; Code:
(require 'cl-lib)
(defsubst dom-tag (node)
"Return the NODE tag."
;; Called on a list of nodes. Use the first.
(if (consp (car node))
(caar node)
(car node)))
(defsubst dom-attributes (node)
"Return the NODE attributes."
;; Called on a list of nodes. Use the first.
(if (consp (car node))
(cadr (car node))
(cadr node)))
(defsubst dom-children (node)
"Return the NODE children."
;; Called on a list of nodes. Use the first.
(if (consp (car node))
(cddr (car node))
(cddr node)))
(defun dom-set-attributes (node attributes)
"Set the attributes of NODE to ATTRIBUTES."
(setq node (dom-ensure-node node))
(setcar (cdr node) attributes))
(defun dom-set-attribute (node attribute value)
"Set ATTRIBUTE in NODE to VALUE."
(setq node (dom-ensure-node node))
(let ((old (assoc attribute (cadr node))))
(if old
(setcdr old value)
(setcar (cdr node) (nconc (cadr node) (list (cons attribute value)))))))
(defmacro dom-attr (node attr)
"Return the attribute ATTR from NODE.
A typical attribute is `href'."
`(cdr (assq ,attr (dom-attributes ,node))))
(defun dom-text (node)
"Return all the text bits in the current node concatenated."
(mapconcat 'identity (cl-remove-if-not 'stringp (dom-children node)) " "))
(defun dom-texts (node &optional separator)
"Return all textual data under NODE concatenated with SEPARATOR in-between."
(mapconcat
'identity
(mapcar
(lambda (elem)
(if (stringp elem)
elem
(dom-texts elem separator)))
(dom-children node))
(or separator " ")))
(defun dom-child-by-tag (dom tag)
"Return the first child of DOM that is of type TAG."
(assoc tag (dom-children dom)))
(defun dom-by-tag (dom tag)
"Return elements in DOM that is of type TAG.
A name is a symbol like `td'."
(let ((matches (cl-loop for child in (dom-children dom)
for matches = (and (not (stringp child))
(dom-by-tag child tag))
when matches
append matches)))
(if (eq (dom-tag dom) tag)
(cons dom matches)
matches)))
(defun dom-by-class (dom match)
"Return elements in DOM that have a class name that matches regexp MATCH."
(dom-elements dom 'class match))
(defun dom-by-style (dom match)
"Return elements in DOM that have a style that matches regexp MATCH."
(dom-elements dom 'style match))
(defun dom-by-id (dom match)
"Return elements in DOM that have an ID that matches regexp MATCH."
(dom-elements dom 'id match))
(defun dom-elements (dom attribute match)
"Find elements matching MATCH (a regexp) in ATTRIBUTE.
ATTRIBUTE would typically be `class', `id' or the like."
(let ((matches (cl-loop for child in (dom-children dom)
for matches = (dom-elements child attribute match)
when matches
append matches))
(attr (dom-attr dom attribute)))
(if (and attr
(string-match match attr))
(cons dom matches)
matches)))
(defun dom-parent (dom node)
"Return the parent of NODE in DOM."
(if (memq node (dom-children dom))
dom
(let ((result nil))
(dolist (elem (dom-children dom))
(when (and (not result)
(not (stringp elem)))
(setq result (dom-parent elem node))))
result)))
(defun dom-node (tag &optional attributes &rest children)
"Return a DOM node with TAG and ATTRIBUTES."
(if children
`(,tag ,attributes ,@children)
(list tag attributes)))
(defun dom-append-child (node child)
"Append CHILD to the end of NODE's children."
(setq node (dom-ensure-node node))
(nconc node (list child)))
(defun dom-add-child-before (node child &optional before)
"Add CHILD to NODE's children before child BEFORE.
If BEFORE is nil, make CHILD NODE's first child."
(setq node (dom-ensure-node node))
(let ((children (dom-children node)))
(when (and before
(not (memq before children)))
(error "%s does not exist as a child" before))
(let ((pos (if before
(cl-position before children)
0)))
(if (zerop pos)
;; First child.
(setcdr (cdr node) (cons child (cddr node)))
(setcdr (nthcdr (1- pos) children)
(cons child (nthcdr pos children))))))
node)
(defun dom-ensure-node (node)
"Ensure that NODE is a proper DOM node."
;; Add empty attributes, if none.
(when (consp (car node))
(setq node (car node)))
(when (= (length node) 1)
(setcdr node (list nil)))
node)
(provide 'dom)
;;; dom.el ends here
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment