parser.lisp

   1 ;;; -*- show-trailing-whitespace: t; indent-tabs: nil -*-
   2
   3 ;;; Copyright (c) 2007 David Lichteblau. All rights reserved.
   4
   5 ;;; Redistribution and use in source and binary forms, with or without
   6 ;;; modification, are permitted provided that the following conditions
   7 ;;; are met:
   8 ;;;
   9 ;;;   * Redistributions of source code must retain the above copyright
  10 ;;;     notice, this list of conditions and the following disclaimer.
  11 ;;;
  12 ;;;   * Redistributions in binary form must reproduce the above
  13 ;;;     copyright notice, this list of conditions and the following
  14 ;;;     disclaimer in the documentation and/or other materials
  15 ;;;     provided with the distribution.
  16 ;;;
  17 ;;; THIS SOFTWARE IS PROVIDED BY THE AUTHOR 'AS IS' AND ANY EXPRESSED
  18 ;;; OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19 ;;; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20 ;;; ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  21 ;;; DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22 ;;; DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  23 ;;; GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  24 ;;; INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  25 ;;; WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  26 ;;; NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  27 ;;; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28
  29 (in-package :xuriella)
  30
  31 (defun map-namespace-declarations (fn element)
  32   (let ((parent (stp:parent element)))
  33     (maphash (lambda (prefix uri)
  34                (unless (and (typep parent 'stp:element)
  35                             (equal (stp:find-namespace prefix parent) uri))
  36                  (funcall fn prefix uri)))
  37              (cxml-stp-impl::collect-local-namespaces element))))
  38
  39 (defun maybe-wrap-namespaces (child exprs)
  40   (if (typep child 'stp:element)
  41       (let ((bindings '())
  42             (excluded-uris '()))
  43         (map-namespace-declarations (lambda (prefix uri)
  44                                       (push (list prefix uri) bindings))
  45                                     child)
  46         (stp:with-attributes ((erp "exclude-result-prefixes" *xsl*))
  47             child
  48           (dolist (prefix (words (or erp "")))
  49             (when (equal prefix "#default")
  50               (setf prefix nil))
  51             (push (or (stp:find-namespace prefix child)
  52                       (xslt-error "namespace not found: ~A" prefix))
  53                   excluded-uris)))
  54         (if bindings
  55             `((xsl:with-namespaces ,bindings
  56                 (xsl:with-excluded-namespaces ,excluded-uris
  57                   ,@exprs)))
  58             exprs))
  59       exprs))
  60
  61 (defun parse-body (node &optional (start 0))
  62   (let ((n (stp:count-children-if #'identity node)))
  63     (labels ((recurse (i)
  64                (when (< i n)
  65                  (let ((child (stp:nth-child i node)))
  66                    (maybe-wrap-namespaces
  67                     child
  68                     (if (namep child "variable")
  69                         (stp:with-attributes (name select) child
  70                           (when (and select (stp:list-children child))
  71                             (xslt-error "variable with select and body"))
  72                           `((let ((,name ,(or select
  73                                               `(progn ,@(parse-body child)))))
  74                               ,@(recurse (1+ i)))))
  75                         (cons (parse-instruction child)
  76                               (recurse (1+ i)))))))))
  77       (recurse start))))
  78
  79 (defun parse-instruction (node)
  80   (typecase node
  81     (stp:element
  82      (if (equal (stp:namespace-uri node) *xsl*)
  83          (parse-instruction/xsl-element
  84           (or (find-symbol (stp:local-name node) :xuriella)
  85               (xslt-error "undefined instruction: ~A" (stp:local-name node)))
  86           node)
  87          (parse-instruction/literal-element node)))
  88     (stp:text
  89      `(xsl:text ,(stp:data node)))))
  90
  91 (defun parse-instruction/literal-element (node)
  92   `(xsl:literal-element
  93        (,(stp:local-name node)
  94          ,(stp:namespace-uri node)
  95          ,(stp:namespace-prefix node))
  96      ,@(stp:map-attributes 'list
  97                            (lambda (a)
  98                              `(xsl:literal-attribute
  99                                   (,(stp:local-name a)
 100                                     ,(stp:namespace-uri a)
 101                                     ,(stp:namespace-prefix a))
 102                                 ,(stp:value a)))
 103                            node)
 104      ,@(parse-body node)))
 105
 106 (defmacro define-instruction-parser (name (node-var) &body body)
 107   `(defmethod parse-instruction/xsl-element
 108        ((.name. (eql ',name)) ,node-var)
 109      (declare (ignore .name.))
 110      ,@body))
 111
 112 (define-instruction-parser |apply-templates| (node)
 113   (stp:with-attributes (select mode) node
 114     `(xsl:apply-templates
 115       (:select ,select :mode ,mode))))
 116
 117 (define-instruction-parser |if| (node)
 118   (stp:with-attributes (test) node
 119     `(when ,test
 120        ,@(parse-body node))))
 121
 122 (define-instruction-parser |choose| (node)
 123   `(cond
 124      ,@(stp:map-children 'list
 125                          (lambda (clause)
 126                            (cond
 127                              ((namep clause "when")
 128                               (stp:with-attributes (test) clause
 129                                 `(,test
 130                                   ,@(parse-body clause))))
 131                              ((namep clause "otherwise")
 132                               `(t ,@(parse-body clause)))
 133                              (t
 134                               (xslt-error "invalid <choose> clause: ~A"
 135                                           (stp:local-name clause)))))
 136                          node)))
 137
 138 (define-instruction-parser |element| (node)
 139   (stp:with-attributes (name namespace use-attribute-sets) node
 140     `(xsl:element (,name :namespace namespace
 141                          :use-attribute-sets use-attribute-sets)
 142        ,@(parse-body node))))
 143
 144 (define-instruction-parser |attribute| (node)
 145   (stp:with-attributes (name namespace) node
 146     `(xsl:attribute (,name :namespace namespace)
 147        ,@(parse-body node))))
 148
 149 (define-instruction-parser |text| (node)
 150   `(xsl:text ,(stp:string-value node)))
 151
 152 (define-instruction-parser |comment| (node)
 153   `(xsl:comment ,@(stp:string-value node)))
 154
 155 (define-instruction-parser |processing-instruction| (node)
 156   (stp:with-attributes (name) node
 157     `(xsl:processing-instruction ,name
 158        ,@(parse-body node))))
 159
 160 (define-instruction-parser |value-of| (node)
 161   (stp:with-attributes (select disable-output-escaping) node
 162     (if disable-output-escaping
 163         `(xsl:unescaped-value-of ,select)
 164         `(xsl:value-of ,select))))
 165
 166 (define-instruction-parser |copy-of| (node)
 167   (stp:with-attributes (select) node
 168     `(xsl:copy-of ,select)))
 169
 170 (define-instruction-parser |copy| (node)
 171   (stp:with-attributes (use-attribute-sets) node
 172     `(xsl:copy (:use-attribute-sets ,use-attribute-sets)
 173                ,@(parse-body node))))
 174
 175 (define-instruction-parser |variable| (node)
 176   (error "unhandled xsl:variable"))
 177
 178 (define-instruction-parser |for-each| (node)
 179   (stp:with-attributes (select) node
 180     (multiple-value-bind (decls body-position)
 181         (loop
 182            for i from 0
 183            for child in (stp:list-children node)
 184            while (namep node "sort")
 185            collect (parse-sort node) into decls
 186            finally (return (values decls i)))
 187       `(xsl:for-each ,select
 188          (declare ,@decls)
 189          ,@(parse-body node body-position)))))
 190
 191 (defun parse-sort (node)
 192   (stp:with-attributes (select lang data-type order case-order) node
 193     `(sort :select ,select
 194            :lang ,lang
 195            :data-type ,data-type
 196            :order ,order
 197            :case-order ,case-order)))
 198
 199 (define-instruction-parser |message| (node)
 200   `(xsl:message ,@(parse-body node)))
 201
 202 (define-instruction-parser |terminate| (node)
 203   `(xsl:terminate ,@(parse-body node)))