tvl-depot/third_party/lisp/s-xml/examples/echo.lisp
Vincent Ambo 437efa7686 feat(third_party/lisp/s-xml): Check in sources & derivation
Checked in the sources for this because it is tracked upstream in CVS
and I can't be bothered to deal with that right now.
2020-01-22 00:49:58 +00:00

64 lines
2 KiB
Common Lisp

;;;; -*- mode: lisp -*-
;;;;
;;;; $Id: echo.lisp,v 1.1 2005/08/17 13:44:30 scaekenberghe Exp $
;;;;
;;;; A simple example as well as a useful tool: parse, echo and pretty print XML
;;;;
;;;; Copyright (C) 2002, 2004 Sven Van Caekenberghe, Beta Nine BVBA.
;;;;
;;;; You are granted the rights to distribute and use this software
;;;; as governed by the terms of the Lisp Lesser General Public License
;;;; (http://opensource.franz.com/preamble.html), also known as the LLGPL.
(in-package :s-xml)
(defun indent (stream count)
(loop :repeat (* count 2) :do (write-char #\space stream)))
(defclass echo-xml-seed ()
((stream :initarg :stream)
(level :initarg :level :initform 0)))
#+NIL
(defmethod print-object ((seed echo-xml-seed) stream)
(with-slots (stream level) seed
(print-unreadable-object (seed stream :type t)
(format stream "level=~d" level))))
(defun echo-xml-new-element-hook (name attributes seed)
(with-slots (stream level) seed
(indent stream level)
(format stream "<~a" name)
(dolist (attribute (reverse attributes))
(format stream " ~a=\'" (car attribute))
(print-string-xml (cdr attribute) stream)
(write-char #\' stream))
(format stream ">~%")
(incf level)
seed))
(defun echo-xml-finish-element-hook (name attributes parent-seed seed)
(declare (ignore attributes parent-seed))
(with-slots (stream level) seed
(decf level)
(indent stream level)
(format stream "</~a>~%" name)
seed))
(defun echo-xml-text-hook (string seed)
(with-slots (stream level) seed
(indent stream level)
(print-string-xml string stream)
(terpri stream)
seed))
(defun echo-xml (in out)
"Parse a toplevel XML element from stream in, echoing and pretty printing the result to stream out"
(start-parse-xml in
(make-instance 'xml-parser-state
:seed (make-instance 'echo-xml-seed :stream out)
:new-element-hook #'echo-xml-new-element-hook
:finish-element-hook #'echo-xml-finish-element-hook
:text-hook #'echo-xml-text-hook)))
;;;; eof