decimal darf mit . starten

[cxml-rng.git] / types.lisp

;;; -*- show-trailing-whitespace: t; indent-tabs: nil -*-
;;;
;;; Copyright (c) 2007 David Lichteblau. All rights reserved.

;;; Redistribution and use in source and binary forms, with or without
;;; modification, are permitted provided that the following conditions
;;; are met:
;;;
;;;   * Redistributions of source code must retain the above copyright
;;;     notice, this list of conditions and the following disclaimer.
;;;
;;;   * Redistributions in binary form must reproduce the above
;;;     copyright notice, this list of conditions and the following
;;;     disclaimer in the documentation and/or other materials
;;;     provided with the distribution.
;;;
;;; THIS SOFTWARE IS PROVIDED BY THE AUTHOR 'AS IS' AND ANY EXPRESSED
;;; OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
;;; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
;;; ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
;;; DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
;;; DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
;;; GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
;;; INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
;;; WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
;;; NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
;;; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

(in-package :cxml-types)

(defstruct (param (:constructor make-param (name value)))
  "@short{A named data type parameter.}

   (With the XSD type library, parameters are known as restricting facets.)
   @see-constructor{make-param}
   @see{find-type}
   @see{cxml-rng:pattern-params}
   @see{cxml-rng:data}
   @see-slot{param-name}
   @see-slot{param-value}"
  name
  value)

(setf (documentation 'make-param 'function)
      "@arg[name]{paramater name, a string}
       @arg[value]{paramater value, a string}
       @return{a @class{param}}
       Create a data type parameter.
       @see{param-name}
       @see{param-value}")

(setf (documentation 'param-name 'function)
      "@arg[instance]{an instance of @class{param}}
       @return{a string}
       The data type parameter's name.
       @see{param-value}")

(setf (documentation 'param-value 'function)
      "@arg[instance]{an instance of @class{param}}
       @return{a string}
       The data type parameter's value.
       @see{param-name}")

(defclass data-type () ()
  (:documentation
   "@short{The abstract superclass of all types.}

    Each type belongs to a datatype library, named by a keyword.  In each
    library, the types are named by strings.

    @see-constructor{find-type}
    @see-slot{type-name}
    @see-slot{type-library}
    @see-slot{type-context-dependent-p}
    @see{parse}
    @see{equal-using-type}
    @see{lessp-using-type}
    @see{validp}"))

(defgeneric find-type (library name params)
  (:documentation
   "@arg[library]{datatype library, a keyword symbol}
    @arg[name]{the type's name, a string}
    @arg[params]{type parameters, a list of @class{param} instances}
    @return{an instance of @class{data-type}, or @code{nil}}
    @short{Look up the type named @em{name} in datatype library @em{library}.}

    Return a type instance for this type and the additional parameters,
    or @code{nil} if the type does not exist.

    Additional parameters (knows as restricting facets in XSD) can be passed
    to specify or restrict the type for the purposes of @fun{validp}.

    @see{data-type}"))

(defgeneric type-library (type)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @return{library name, a keyword}
    @short{Return the name of the library this type belongs to.}

    @see{type-name}
    @see{type-context-dependent-p}"))

(defgeneric type-name (type)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @return{type name, a string}
    @short{Return the name this type has within its library.}

    @see{type-library}
    @see{type-context-dependent-p}"))

(defmethod find-type ((library t) name params)
  (declare (ignore name params))
  nil)

(defgeneric type-context-dependent-p (type)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @return{a boolean}
    @short{Return true if parsing and validation of values by this type
      depends on the validation context.}

    In this case, the optional @code{context} argument to @fun{parse} and
    @fun{validp} is required, and an error will be signalled if it is missing.

    @see{validation-context}
    @see{type-name}
    @see{type-library}
    @see{type-context-dependent-p}"))

(defmethod type-context-dependent-p ((type data-type))
  nil)

(defgeneric equal-using-type (type u v)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @arg[u]{a parsed value as returned by @fun{parse}}
    @arg[v]{a parsed value as returned by @fun{parse}}
    @return{a boolean}
    @short{Compare the @emph{values} @code{u} and @code{v} using a
      data-type-dependent equality function.}

    @see{validp}"))

(defgeneric parse (type e &optional context)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @arg[e]{a string}
    @arg[context]{an instance of @class{validation-context}}
    @return{an object}
    @short{Parse string @code{e} and return a representation of its value
      as defined by the data type.}

    The @code{context} argument is required if @fun{type-context-dependent-p}
    is true for @code{type}, and will be ignored otherwise.

    @see{equal-using-type}
    @see{validp}"))

(defgeneric validp (type e &optional context)
  (:documentation
   "@arg[type]{an instance of @class{data-type}}
    @arg[e]{a string}
    @arg[context]{an instance of @class{validation-context}}
    @return{a boolean}
    @short{Determine whether a string is a valid lexical representation
    for a type.}

    The @code{context} argument is required if @fun{type-context-dependent-p}
    is true for @code{type}, and will be ignored otherwise.

    @see{parse}
    @see{equal-using-type}"))


;;; Validation context

(defclass validation-context () ()
  (:documentation
   "@short{This abstract class defines a protocol allowing data types
    to query the XML parser about its current state.}

    Some types are context dependent, as indicated by
    @fun{type-context-dependent-p}.  Those types need access to state
    computed by the XML parser implicitly, like namespace bindings or
    the Base URI.

    User-defined subclasses must implement methods
    for the functions @fun{context-find-namespace-binding} and
    @fun{context-find-unparsed-entity}.

    Two pre-defined validation context implementations are
    provided, one for use with SAX, the other based on Klacks."))

(defgeneric context-find-namespace-binding (context prefix)
  (:documentation
   "@arg[context]{an instance of @class{validation-context}}
    @arg[prefix]{name prefix, a string}
    @return{the namespace URI as a string, or NIL}
    @short{This function resolves a namespace prefix to a namespace URI in the
    current context.}
    All currently declared namespaces
    are taken into account, including those declared directly on the
    current element."))

(defgeneric context-find-unparsed-entity (context name)
  (:documentation
   "@arg[context]{an instance of @class{validation-context}}
    @arg[name]{entity name, a string}
    @return{@code{nil}, or a list of public id, system id, and notation name}
    This function looks for an unparsed entity in the current context."))

(defclass klacks-validation-context (validation-context)
  ((source :initarg :source :accessor context-source))
  (:documentation
   "A validation-context implementation that queries
    a klacks source for information about the parser's current state.
    @see-constructor{make-klacks-validation-context}"))

(defun make-klacks-validation-context (source)
  "@arg[source]{a @a[http://common-lisp.net/project/cxml/klacks.html]{
     klacks source}}
   @return{a @class{klacks-validation-context}}
   Create a validation-context that will query the given klacks source for
   the current parser context."
  (make-instance 'klacks-validation-context :source source))

(defmethod context-find-namespace-binding
    ((context klacks-validation-context) prefix)
  (klacks:find-namespace-binding prefix (context-source context)))

;; zzz nicht schoen.
(defmethod context-find-unparsed-entity
    ((context klacks-validation-context) name)
  (or (dolist (x (slot-value (context-source context)
                             'cxml::external-declarations))
        (when (and (eq (car x) 'sax:unparsed-entity-declaration)
                   (equal (cadr x) name))
          (return t)))
      (dolist (x (slot-value (context-source context)
                             'cxml::internal-declarations))
        (when (and (eq (car x) 'sax:unparsed-entity-declaration)
                   (equal (cadr x) name))
          (return t)))))

(defclass sax-validation-context-mixin (validation-context)
  ((stack :initform nil :accessor context-stack)
   (unparsed-entities :initform (make-hash-table :test 'equal)
                      :accessor unparsed-entities))
  (:documentation
   "@short{A class that implements validation-context as a mixin for
     user-defined SAX handler classes.}

    The mixin will record namespace information
    automatically, and the user's SAX handler can simply be passed as a
    validation context to data type functions."))

(defmethod sax:start-prefix-mapping
    ((handler sax-validation-context-mixin) prefix uri)
  (push (cons prefix uri) (context-stack handler)))

(defmethod sax:end-prefix-mapping
    ((handler sax-validation-context-mixin) prefix)
  (setf (context-stack handler)
        (remove prefix
                (context-stack handler)
                :count 1
                :key #'car
                :test #'equal)))

(defmethod sax:unparsed-entity-declaration
    ((context sax-validation-context-mixin)
     name public-id system-id notation-name)
  (setf (gethash name (unparsed-entities context))
        (list public-id system-id notation-name)))

(defmethod context-find-namespace-binding
    ((context sax-validation-context-mixin) prefix)
  (cdr (assoc prefix (context-stack context) :test #'equal)))

(defmethod context-find-unparsed-entity
    ((context sax-validation-context-mixin) name)
  (gethash name (unparsed-entities context)))


;;; Relax NG built-in type library

(defclass rng-type (data-type) ()
  (:documentation
   "@short{The class of Relax NG built-in types.}
    Relax NG defines two built-in data type: string and token.

    The Relax NG type library is named @code{:||}."))

(defclass string-type (rng-type) ()
  (:documentation
   "@short{The Relax NG 'string' type.}
    This data type allows arbitrary strings and interprets them as-is.

    For this type, @fun{parse} will return any string unchanged, and
    @fun{equal-using-type} compares strings using @code{equal}."))

(defclass token-type (rng-type) ()
  (:documentation
   "@short{The Relax NG 'token' type.}
    This data type allows arbitrary strings and normalizes all whitespaces.

    For this type, @fun{parse} will return the string with leading and
    trailing whitespace removed, and remaining sequences of spaces
    compressed down to one space character each.

    A method for @fun{equal-using-type} compares strings using @code{equal}."))

(defmethod type-library ((type rng-type))
  :||)

(defvar *string-data-type* (make-instance 'string-type))
(defvar *token-data-type* (make-instance 'token-type))

(defmethod find-type ((library (eql :||)) name params)
  (cond
    ((eq name :probe) t)
    (params :error)
    ((equal name "string") *string-data-type*)
    ((equal name "token") *token-data-type*)
    (t nil)))

(defmethod equal-using-type ((type rng-type) u v)
  (equal u v))

(defmethod validp ((type rng-type) e &optional context)
  (declare (ignore e context))
  t)

(defmethod type-name ((type string-type)) "string")
(defmethod type-name ((type token-type)) "token")

(defmethod parse ((type string-type) e &optional context)
  (declare (ignore context))
  e)

(defmethod parse ((type token-type) e &optional context)
  (declare (ignore context))
  (normalize-whitespace e))

(eval-when (:compile-toplevel :load-toplevel :execute)
  (defparameter *whitespace*
    (format nil "~C~C~C~C"
            (code-char 9)
            (code-char 32)
            (code-char 13)
            (code-char 10))))

(defun normalize-whitespace (str)
  (cl-ppcre:regex-replace-all #.(format nil "[~A]+" *whitespace*)
                              (string-trim *whitespace* str)
                              " "))

(defun replace-whitespace (str)
  (cl-ppcre:regex-replace-all #.(format nil "[~A]" *whitespace*)
                              str
                              " "))


;;; XML Schema Part 2: Datatypes Second Edition

(defparameter *xsd-types* (make-hash-table :test 'equal))

(defmacro defxsd
    ((class-name type-name) (&rest supers) (&rest slots) &rest args)
  `(progn
     (setf (gethash ,type-name *xsd-types*) ',class-name)
     (defclass ,class-name ,supers
         ((type-name :initform ,type-name
                     :reader type-name
                     :allocation :class)
          ,@slots)
       ,@args)))

(defclass xsd-type (data-type)
  ((patterns :initform nil :initarg :patterns :reader patterns))
  (:documentation
   "@short{The class of XML Schema built-in types.}

    Subclasses of xsd-type provide the built-in types of
    @a[http://www.w3.org/TR/xmlschema-2/]{
      XML Schema Part 2: Datatypes Second Edition}
    as specified in @a[http://relaxng.org/xsd-20010907.html]{Guidelines for
    using W3C XML Schema Datatypes with RELAX NG}.

    The XSD type library
    is named @code{:|http://www.w3.org/2001/XMLSchema-datatypes|}."))

(defmethod type-library ((type xsd-type))
  :|http://www.w3.org/2001/XMLSchema-datatypes|)

(defun zip (keys values)
  (loop for key in keys for value in values collect key collect value))

(defgeneric parse-parameter (class-name type-name param-name value))

(defun parse-parameters (type-class params)
  (let ((patterns '())
        (args '()))
    (dolist (param params (values t patterns args))
      (let ((name (param-name param))
            (value (param-value param)))
        (if (equal name "pattern")
            (push value patterns)
            (multiple-value-bind (key required-class)
                (case (find-symbol (param-name param) :keyword)
                  (:|length| (values :exact-length 'length-mixin))
                  (:|maxLength| (values :max-length 'length-mixin))
                  (:|minLength| (values :min-length 'length-mixin))
                  (:|minInclusive| (values :min-inclusive 'ordering-mixin))
                  (:|maxInclusive| (values :max-inclusive 'ordering-mixin))
                  (:|minExclusive| (values :min-exclusive 'ordering-mixin))
                  (:|maxExclusive| (values :max-exclusive 'ordering-mixin))
                  (:|totalDigits| (values :total-digits 'decimal-type))
                  (:|fractionDigits| (values :fraction-digits 'decimal-type))
                  (t (return nil)))
              (unless (subtypep type-class required-class)
                (return nil))
              (when (loop
                       for (k nil) on args by #'cddr
                       thereis (eq key k))
                (return nil))
              (push (parse-parameter required-class type-class key value) args)
              (push key args)))))))

(defmethod find-type
    ((library (eql :|http://www.w3.org/2001/XMLSchema-datatypes|)) name params)
  (if (eq name :probe)
      t
      (let ((class (gethash name *xsd-types*)))
        (if class
            (multiple-value-bind (ok patterns other-args)
                (parse-parameters class params)
              (if ok
                  (apply #'make-instance
                         class
                         :patterns patterns
                         other-args)
                  :error))
            nil))))

(defgeneric parse/xsd (type e context))

(defgeneric validp/xsd (type v context)
  (:method-combination and))

(defmethod validp/xsd and ((type xsd-type) v context)
  (declare (ignore context))
  ;; zzz
  #+(or)
  (every (lambda (pattern)
           (cl-ppcre:all-matches pattern v))
         (patterns type))
  t)

(defmethod validp ((type xsd-type) e &optional context)
  (not (eq :error (parse/xsd type e context))))

(defmethod parse ((type xsd-type) e &optional context)
  (let ((result (parse/xsd type e context)))
    (when (eq result :error)
      (error "not valid for data type ~A: ~S" type e))
    result))

;; Handle the whiteSpace "facet" before the subclass sees it.
;; If parsing succeded, check other facets by asking validp/xsd.
(defmethod parse/xsd :around ((type xsd-type) e context)
  (let ((result (call-next-method type
                                  (munge-whitespace type e)
                                  context)))
    (if (or (eq result :error) (validp/xsd type result context))
        result
        :error)))

(defgeneric munge-whitespace (type e))

(defmethod munge-whitespace ((type xsd-type) e)
  (normalize-whitespace e))


;;; ordering-mixin

(defclass ordering-mixin ()
    ((min-exclusive :initform nil
                    :initarg :min-exclusive
                    :accessor min-exclusive)
     (max-exclusive :initform nil
                    :initarg :max-exclusive
                    :accessor max-exclusive)
     (min-inclusive :initform nil
                    :initarg :min-inclusive
                    :accessor min-inclusive)
     (max-inclusive :initform nil
                    :initarg :max-inclusive
                    :accessor max-inclusive)))

(defmethod parse-parameter
    ((class-name (eql 'ordering-mixin)) type-name (param t) value)
  (parse (make-instance type-name) value nil))

(defgeneric lessp-using-type (type u v)
  (:documentation
   "@arg[type]{an ordered @class{data-type}}
    @arg[u]{a parsed value as returned by @fun{parse}}
    @arg[v]{a parsed value as returned by @fun{parse}}
    @return{a boolean}
    @short{Compare the @emph{values} @code{u} and @code{v} using a
      data-type-dependent partial ordering.}

    A method for this function is provided only by types that have a
    natural partial ordering.  The ordering is described in the
    documentation for the type.

    @see{equal-using-type}"))

(defun <-using-type (type u v)
  (lessp-using-type type u v))

(defun <=-using-type (type u v)
  (or (lessp-using-type type u v) (equal-using-type type u v)))

;; it's only a partial ordering, so in general this is not the opposite of <=
(defun >-using-type (type u v)
  (lessp-using-type type v u))

;; it's only a partial ordering, so in general this is not the opposite of <
(defun >=-using-type (type u v)
  (or (lessp-using-type type v u) (equal-using-type type v u)))

(defmethod validp/xsd and ((type ordering-mixin) v context)
  (declare (ignore context))
  (with-slots (min-exclusive max-exclusive min-inclusive max-inclusive) type
    (and (or (null min-exclusive) (>-using-type type v min-exclusive))
         (or (null max-exclusive) (<-using-type type v max-exclusive))
         (or (null min-inclusive) (>=-using-type type v min-inclusive))
         (or (null max-inclusive) (<=-using-type type v max-inclusive)))))


;;; length-mixin

(defclass length-mixin ()
    ((exact-length :initform nil :initarg :exact-length :accessor exact-length)
     (min-length :initform nil :initarg :min-length :accessor min-length)
     (max-length :initform nil :initarg :max-length :accessor max-length)))

(defmethod parse-parameter
    ((class-name (eql 'length-mixin)) (type-name t) (param t) value)
  (parse (make-instance 'non-negative-integer-type) value nil))

;; extra-hack fuer die "Laenge" eines QName...
(defgeneric length-using-type (type u))
(defmethod length-using-type ((type length-mixin) e) (length e))

(defmethod validp/xsd and ((type length-mixin) v context)
  (declare (ignore context))
  (with-slots (exact-length min-length max-length) type
    (or (not (or exact-length min-length max-length))
        (let ((l (length-using-type type v)))
          (and (or (null exact-length) (eql l exact-length))
               (or (null min-length) (>= l min-length))
               (or (null max-length) (<= l max-length)))))))


;;; enumeration-type

(defclass enumeration-type (xsd-type length-mixin)
    ((word-type :reader word-type)))

(defmethod initialize-instance :after ((type enumeration-type) &key)
  (setf (min-length type) (max* 1 (min-length type))))

(defmethod parse/xsd ((type enumeration-type) e context)
  (let ((wt (word-type type)))
    (loop
       for word in (cl-ppcre:split " " e)
       for v = (parse wt word context)
       collect v
       when (eq v :error) do (return :error))))



;;;; Primitive types

;;; duration

(defxsd (duration-type "duration") (xsd-type ordering-mixin) ())

(defmethod equal-using-type ((type duration-type) u v)
  (equal u v))

;; zzz das ist vielleicht ein bisschen zu woertlich implementiert
(defmethod lessp-using-type ((type duration-type) u v)
  (let ((dt (make-instance 'date-time-type)))
    (every (lambda (str)
             (let ((s (parse dt str nil)))
               (lessp-using-type dt
                                 (datetime+duration s u)
                                 (datetime+duration s v))))
           '("1696-09-01T00:00:00Z"
             "1697-02-01T00:00:00Z"
             "1903-03-01T00:00:00Z"
             "1903-07-01T00:00:00Z"))))

(defun datetime+duration (s d)
  (destructuring-bind (syear smonth sday shour sminute ssecond szone) s
    (destructuring-bind (dyear dmonth dday dhour dminute dsecond) d
      (labels ((floor3 (a low high)
                 (multiple-value-bind (u v)
                     (floor (- a low) (- high low))
                   (values u (+ low v))))
               (maximum-day-in-month-for (yearvalue monthvalue)
                 (multiple-value-bind (m y)
                     (floor3 monthvalue 1 13)
                   (day-limit m (+ yearvalue y)))))
        (multiple-value-bind (carry emonth) (floor3 (+ smonth dmonth) 1 13)
          (let ((eyear (+ syear dyear carry))
                (ezone szone))
            (multiple-value-bind (carry esecond) (floor (+ ssecond dsecond) 60)
              (multiple-value-bind (carry eminute)
                  (floor (+ sminute dminute carry) 60)
                (multiple-value-bind (carry ehour)
                    (floor (+ shour dhour carry) 24)
                  (let* ((mdimf (maximum-day-in-month-for eyear emonth))
                         (tmpdays (max 1 (min sday mdimf)))
                         (eday (+ tmpdays dday carry)))
                    (loop
                       (let* ((mdimf (maximum-day-in-month-for eyear emonth))
                              (carry
                               (cond
                                 ((< eday 1)
                                  (setf eday (+ eday mdimf))
                                  -1)
                                 ((> eday mdimf)
                                  (setf eday (- eday mdimf))
                                  1)
                                 (t
                                  (return))))
                              (tmp (+ emonth carry)))
                         (multiple-value-bind (y m)
                             (floor3 tmp 1 13)
                           (setf emonth m)
                           (incf eyear y))))
                    (list eyear emonth eday ehour eminute esecond
                          ezone)))))))))))

(defun scan-to-strings (&rest args)
  (coerce (nth-value 1 (apply #'cl-ppcre:scan-to-strings args)) 'list))

(defmethod parse/xsd ((type duration-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional minusp y m d tp h min s)
      (scan-to-strings "(?x)
                         ^(-)?            # minus
                         P(?:(\\d+)Y)?    # years
                         (?:(\\d+)M)?     # months
                         (?:(\\d+)D)?     # days
                         (T               # (time)
                           (?:(\\d+)H)?   # hours
                           (?:(\\d+)M)?   # minutes
                           (?:(\\d+(?:[.]\\d+)?)S)?   # seconds
                           )?$"
                       e)
    (if (and (or y m d h min s)
             (or (null tp) (or h min s)))
        (let ((f (if minusp -1 1)))
          (flet ((int (str)
                   (and str (* f (parse-integer str)))))
            (list (int y) (int m) (int d) (int h) (int min)
                  (and s (* f (parse-number:parse-number s))))))
        :error)))


;;; dateTime

(defclass time-ordering-mixin (ordering-mixin) ())

(defxsd (date-time-type "dateTime") (xsd-type time-ordering-mixin) ())

(defmethod equal-using-type ((type time-ordering-mixin) u v)
  (equal u v))

;; add zone-offset as a duration (if any), but keep a boolean in the
;; zone-offset field indicating whether there was a time-zone
(defun normalize-date-time (u)
  (destructuring-bind (year month day hour minute second zone-offset) u
    (let ((v (list year month day hour minute second (and zone-offset t))))
      (if zone-offset
          (multiple-value-bind (h m)
              (truncate zone-offset)
            (datetime+timezone v h (* m 100)))
          v))))

(defun datetime+timezone (d h m)
  (datetime+duration d (list 0 0 0 h m 0)))

(defmethod lessp-using-type ((type time-ordering-mixin) p q)
  (destructuring-bind (pyear pmonth pday phour pminute psecond pzone)
      (normalize-date-time p)
    (destructuring-bind (qyear qmonth qday qhour qminute qsecond qzone)
        (normalize-date-time q)
      (cond
        ((and pzone (not qzone))
         (lessp-using-type type p (datetime+timezone q 14 0)))
        ((and (not pzone) qzone)
         (lessp-using-type type (datetime+timezone p -14 0) q))
        (t
         ;; zzz hier sollen wir <> liefern bei Feldern, die in genau einer
         ;; der Zeiten fehlen.  Wir stellen aber fehlende Felder derzeit
         ;; defaulted dar, koennen diese Situation also nicht feststellen.
         ;; Einen Unterschied sollte das nur machen, wenn Werte verschiedener
         ;; Datentypen miteinander verglichen werden.  Das bieten wir einfach
         ;; nicht an.
         (loop
            for a in (list pyear pmonth pday phour pminute psecond)
            for b in (list qyear qmonth qday qhour qminute qsecond)
            do
              (when (< a b)
                (return t))
              (when (> a b)
                (return nil))))))))

(defun day-limit (m y)
  (cond
    ((and (eql m 2)
          (or (zerop (mod y 400))
              (and (zerop (mod y 4))
                   (not (zerop (mod y 100))))))
     29)
    ((eql m 2) 28)
    ((oddp y) 31)
    (t 30)))

(defmethod parse-time (minusp y m d h min s tz tz-sign tz-h tz-m
                       &key (start 0) end)
  (declare (ignore start end))          ;zzz
  ;; parse into numbers
  (flet ((int (str)
           (and str (parse-integer str)))
         (num (str)
           (and str (parse-number:parse-number str))))
    (setf (values y m d h min s tz-h tz-m)
          (values (* (int y) (if minusp -1 1))
                  (int m) (int d) (int h) (int min)
                  (num s)
                  (int tz-h) (int tz-m))))
  (let ((day-limit (day-limit m y)))
    ;; check ranges
    (cond
      ((and y
            (plusp y)
            (<= 1 m 12)
            (<= 1 d day-limit)
            (<= 0 h 24)
            (<= 0 m 59)
            ;; zzz sind leap seconds immer erlaubt?
            (<= 0 s 60))
       ;; 24:00:00 must be canonicalized
       (when (and (eql h 24) (zerop min) (zerop s))
         (incf h)
         (incf d)
         (when (> d day-limit)
           (setf d 1)
           (incf m)
           (when (> m 12)
             (incf y))))
       (let ((tz-offset
              (when tz-h
                (* (if (equal tz-sign "-") -1 1)
                   (+ tz-h (/ tz-m 100))))))
         (list (* y (if minusp -1 1)) m d h min s tz-offset)
         ;; (subseq ... start end)
         ))
      (t
       :error))))

(defmethod parse/xsd ((type date-time-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional minusp y m d h min s tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^(-)?                     # opt. minus
                          ((?:[1-9]\\d*)?\\d{4})      # year
                          -(\\d\\d)                   # month
                          -(\\d\\d)                   # day
                          T                         # (time)
                          (\\d\\d)                    # hour
                          -(\\d\\d)                   # minute
                          -(\\d+(?:[.]\\d+)?)        # second
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time minusp y m d h min s tz tz-sign tz-h tz-m)))


;;; time

(defxsd (time-type "time") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type time-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional h min s tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^(\\d\\d)                    # hour
                          -(\\d\\d)                   # minute
                          -(\\d+(?:[.]\\d+)?)        # second
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time nil 1 1 1 h min s tz tz-sign tz-h tz-m
                :start 3)))


;;; date

(defxsd (date-type "date") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type date-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional minusp y m d tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^(-)?                     # opt. minus
                          ((?:[1-9]\\d*)?\\d{4})      # year
                          -(\\d\\d)                   # month
                          -(\\d\\d)                   # day
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time minusp y m d 0 0 0 tz tz-sign tz-h tz-m
                :end 3)))


;;; gYearMonth

(defxsd (year-month-type "gYearMonth") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type year-month-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional minusp y m)
      (scan-to-strings "(?x)
                          ^(-)?                     # opt. minus
                          ((?:[1-9]\\d*)?\\d{4})      # year
                          -(\\d\\d)                   # month
                          $"
                       e)
    (parse-time minusp y m 1 0 0 0 nil nil nil nil
                :end 2)))


;;; gYear

(defxsd (year-type "gYear") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type year-month-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional minusp y tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^(-)?                     # opt. minus
                          ((?:[1-9]\\d*)?\\d{4})      # year
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time minusp y 1 1 0 0 0 tz tz-sign tz-h tz-m
                :end 1)))


;;; gMonthDay

(defxsd (month-day-type "gMonthDay") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type month-day-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional m d tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^--(\\d\\d)                 # month
                          -(\\d\\d)                   # day
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time nil 1 m d 0 0 0 tz tz-sign tz-h tz-m
                :start 1 :end 3)))


;;; gDay

(defxsd (day-type "gDay") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type day-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional d tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ---(\\d\\d)                   # day
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time nil 1 1 d 0 0 0 tz tz-sign tz-h tz-m
                :start 3 :end 4)))


;;; gMonth

(defxsd (month-type "gMonth") (xsd-type time-ordering-mixin) ())

(defmethod parse/xsd ((type month-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional m tz tz-sign tz-h tz-m)
      (scan-to-strings "(?x)
                          ^--(\\d\\d)                 # month
                          (([+-])(\\d\\d):(\\d\\d)|Z)?  # opt timezone
                          $"
                       e)
    (parse-time nil 1 m 1 0 0 0 tz tz-sign tz-h tz-m
                :start 2 :end 3)))


;;; boolean

(defxsd (boolean-type "boolean") (xsd-type) ())

(defmethod parse/xsd ((type boolean-type) e context)
  (declare (ignore context))
  (case (find-symbol e :keyword)
    ((:|true| :|1|) t)
    ((:|false| :|0|) nil)))


;;; base64Binary

(defxsd (base64-binary-type "base64Binary") (xsd-type length-mixin) ())

(defmethod equal-using-type ((type base64-binary-type) u v)
  (equalp u v))

(defmethod parse/xsd ((type base64-binary-type) e context)
  (declare (ignore context))
  (if (cl-ppcre:all-matches
       "(?x)
        ^(([A-Za-z0-9+/][ ]?[A-Za-z0-9+/][ ]?[A-Za-z0-9+/]
                  [ ]?[A-Za-z0-9+/][ ]?)*
           (([A-Za-z0-9+/][ ]?[A-Za-z0-9+/][ ]?[A-Za-z0-9+/][ ]?[A-Za-z0-9+/])
             | ([A-Za-z0-9+/][ ]?[A-Za-z0-9+/][ ]?[AEIMQUYcgkosw048][ ]?=)
             | ([A-Za-z0-9+/][ ]?[AQgw][ ]?=[ ]?=)))?$"
       e)
      (handler-case
          (cl-base64:base64-string-to-usb8-array e)
        (warning (c)
          (error "unexpected failure in Base64 decoding: ~A" c)))
      :error))


;;; hexBinary

(defxsd (hex-binary-type "hexBinary") (xsd-type length-mixin) ())

(defmethod equal-using-type ((type hex-binary-type) u v)
  (equalp u v))

(defmethod parse/xsd ((type hex-binary-type) e context)
  (declare (ignore context))
  (if (evenp (length e))
      (let ((result
             (make-array (/ (length e) 2) :element-type '(unsigned-byte 8))))
        (loop
           for i from 0 below (length e) by 2
           for j from 0
           do
             (setf (elt result j)
                   (handler-case
                       (parse-integer e :start i :end (+ i 2) :radix 16)
                     (error ()
                       (return :error))))
           finally (return result)))
      :error))


;;; float

(defxsd (float-type "float") (xsd-type ordering-mixin) ())

(defmethod equal-using-type ((type float-type) u v)
  (= u v))

(defmethod lessp-using-type ((type float-type) u v)
  (< u v))

;; zzz nehme hier an, dass single-float in IEEE single float ist.
;; Das stimmt unter LispWorks bestimmt wieder nicht.
(defmethod parse/xsd ((type float-type) e context)
  (declare (ignore context))
  (if (cl-ppcre:all-matches "^[+-]?\\d+([.]\\d+)?([eE][+-]?\\d+)?$" e)
      (coerce (parse-number:parse-number e) 'single-float)
      :error))


;;; decimal

(defxsd (decimal-type "decimal") (xsd-type ordering-mixin)
  ((fraction-digits :initform nil
                    :initarg :fraction-digits
                    :accessor fraction-digits)
   (total-digits :initform nil
                 :initarg :total-digits
                 :accessor total-digits)))

(defmethod parse-parameter
    ((class-name (eql 'decimal-type))
     (type-name t)
     (param (eql :fraction-digits))
     value)
  (parse (make-instance 'non-negative-integer-type) value nil))

(defmethod parse-parameter
    ((class-name (eql 'decimal-type))
     (type-name t)
     (param (eql :total-digits))
     value)
  (parse (make-instance 'positive-integer-type) value nil))

(defmethod lessp-using-type ((type decimal-type) u v)
  (< u v))

(defmethod equal-using-type ((type decimal-type) u v)
  (= u v))

(defmethod validp/xsd and ((type decimal-type) v context)
  (declare (ignore context))
  (with-slots (fraction-digits total-digits) type
    (and (or (null fraction-digits)
             (let* ((betrag (abs v))
                    (fraction (- betrag (truncate betrag)))
                    (scaled (* fraction (expt 10 fraction-digits))))
               (zerop (mod scaled 1))))
         (or (null total-digits)
             (let ((scaled (abs v)))
               (loop
                  until (zerop (mod scaled 1))
                  do (setf scaled (* scaled 10)))
               (< scaled (expt 10 total-digits)))))))

(defmethod parse/xsd ((type decimal-type) e context)
  (declare (ignore context))
  (destructuring-bind (&optional a b)
      (scan-to-strings "^([+-]?\\d*)(?:[.](\\d+))?$" e)
    (if (plusp (+ (length a) (length b)))
        (+ (if (plusp (length a))
               (parse-integer a)
               0)
           (if (plusp (length b))
               (/ (parse-integer b) (expt 10 (length b)))
               0))
        :error)))


;;; double

(defxsd (double-type "double") (xsd-type ordering-mixin) ())

(defmethod equal-using-type ((type double-type) u v)
  (= u v))

(defmethod lessp-using-type ((type double-type) u v)
  (< u v))

;; zzz nehme hier an, dass double-float in IEEE double float ist.
;; Auch das ist nicht garantiert.
(defmethod parse/xsd ((type double-type) e context)
  (declare (ignore context))
  (if (cl-ppcre:all-matches "^[+-]?\\d+([.]\\d+)?([eE][+-]?\\d+)?$" e)
      (coerce (parse-number:parse-number e) 'double-float)
      :error))


;;; AnyURi

(defxsd (any-uri-type "anyURI") (xsd-type length-mixin) ())

(defmethod equal-using-type ((type any-uri-type) u v)
  (equal u v))

(defmethod parse/xsd ((type any-uri-type) e context)
  (cxml-rng::escape-uri e))


;;; QName
;;; NOTATION

(defclass qname-like (xsd-type length-mixin) ())

(defxsd (qname-type "QName") (qname-like) ())
(defxsd (notation-type "NOTATION") (qname-like) ())

(defstruct (qname (:constructor make-qname (uri lname length)))
  uri
  lname
  length)

(defmethod length-using-type ((type qname-like) e)
  (qname-length e))

(defmethod equal-using-type ((type qname-like) u v)
  (and (equal (qname-uri u) (qname-uri v))
       (equal (qname-lname u) (qname-lname v))))

(defun namep (str)
  (and (not (zerop (length str)))
       (cxml::name-start-rune-p (elt str 0))
       (every #'cxml::name-rune-p str)))

(defmethod parse/xsd ((type qname-like) e context)
  (handler-case
      (if (namep e)
          (multiple-value-bind (prefix local-name) (cxml::split-qname e)
            (let ((uri (when prefix
                         (context-find-namespace-binding context prefix))))
              (if (and prefix (not uri))
                  :error
                  (make-qname uri local-name (length e)))))
          :error)
    (cxml:well-formedness-violation ()
      :error)))


;;; string

(defxsd (xsd-string-type "string") (xsd-type length-mixin) ())

(defmethod equal-using-type ((type xsd-string-type) u v)
  (equal u v))

(defmethod munge-whitespace ((type xsd-string-type) e)
  e)

(defmethod parse/xsd ((type xsd-string-type) e context)
  e)


;;;;
;;;; Derived types
;;;;

;;; normalizedString

(defxsd (normalized-string-type "normalizedString") (xsd-string-type) ())

(defmethod munge-whitespace ((type normalized-string-type) e)
  (replace-whitespace e))


;;; token

(defxsd (xsd-token-type "token") (normalized-string-type) ())

(defmethod munge-whitespace ((type xsd-token-type) e)
  (normalize-whitespace e))


;;; language

(defxsd (language-type "language") (xsd-token-type)
  ((patterns :initform '("[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*"))))


;;; Name

(defxsd (name-type "Name") (xsd-token-type)
  ((patterns :initform '("\\i\\c*"))))


;;; NCName

(defxsd (ncname-type "NCName") (name-type)
  ((patterns :initform '("[\\i-[:]][\\c-[:]]*"))))

(defmethod equal-using-type ((type ncname-type) u v)
  (equal u v))

(defun nc-name-p (str)
  (and (namep str) (cxml::nc-name-p str)))

(defmethod parse/xsd ((type ncname-type) e context)
  ;; zzz mit pattern machen
  (if (nc-name-p e)
      e
      :error))

;;; ID

(defxsd (id-type "ID") (ncname-type) ())


;;; IDREF

(defxsd (idref-type "IDREF") (id-type) ())


;;; IDREFS

(defxsd (idrefs-type "IDREFS") (enumeration-type)
  ((word-type :initform (make-instance 'idref-type))))


;;; ENTITY

(defxsd (entity-type "ENTITY") (ncname-type) ())

(defmethod parse/xsd ((type entity-type) e context)
  (if (context-find-unparsed-entity context e)
      e
      :error))


;;; ENTITIES

(defxsd (entities-type "ENTITIES") (enumeration-type)
  ((word-type :initform (make-instance 'entity-type))))


;;; NMTOKEN

(defxsd (nmtoken-type "NMTOKEN") (xsd-token-type)
  ((patterns :initform '("\\c+"))))


;;; NMTOKENS

(defxsd (nmtokens-type "NMTOKENS") (enumeration-type)
  ((word-type :initform (make-instance 'nmtoken-type))))


;;; integer

(defxsd (integer-type "integer") (decimal-type) ())

;; period is forbidden, so there's no point in letting decimal handle parsing
;; fixme: sind fuehrende nullen nun erlaubt oder nicht?  die spec sagt ja,
;; das pattern im schema nicht.
(defmethod parse/xsd ((type integer-type) e context)
  (declare (ignore context))
  (if (cl-ppcre:all-matches "^[+-]?(?:[1-9]\\d*|0)$" e)
      (parse-number:parse-number e)
      :error))


;;; nonPositiveInteger

(defxsd (non-positive-integer-type "nonPositiveInteger") (integer-type) ())

(defun min* (a b)
  (cond
    ((null a) b)
    ((null b) a)
    (t (min a b))))

(defun max* (a b)
  (cond
    ((null a) b)
    ((null b) a)
    (t (max a b))))

(defmethod initialize-instance :after ((type non-positive-integer-type) &key)
  (setf (max-inclusive type)
        (min* 0 (max-inclusive type))))


;;; nonPositiveInteger

(defxsd (negative-integer-type "negativeInteger") (non-positive-integer-type)
  ())

(defmethod initialize-instance :after ((type negative-integer-type) &key)
  (setf (max-inclusive type)
        (min* -1 (max-inclusive type))))


;;; long

(defxsd (long-type "long") (integer-type) ())

(defmethod initialize-instance :after ((type long-type) &key)
  (setf (max-inclusive type) (min* 9223372036854775807 (max-inclusive type)))
  (setf (min-inclusive type) (max* -9223372036854775808 (min-inclusive type))))


;;; int

(defxsd (int-type "int") (long-type) ())

(defmethod initialize-instance :after ((type int-type) &key)
  (setf (max-inclusive type) (min* 2147483647 (max-inclusive type)))
  (setf (min-inclusive type) (max* -2147483648 (min-inclusive type))))


;;; short

(defxsd (short-type "short") (int-type) ())

(defmethod initialize-instance :after ((type short-type) &key)
  (setf (max-inclusive type) (min* 32767 (max-inclusive type)))
  (setf (min-inclusive type) (max* -32768 (min-inclusive type))))


;;; byte

(defxsd (byte-type "byte") (short-type) ())

(defmethod initialize-instance :after ((type byte-type) &key)
  (setf (max-inclusive type) (min* 127 (max-inclusive type)))
  (setf (min-inclusive type) (max* -128 (min-inclusive type))))


;;; nonNegativeInteger

(defxsd (non-negative-integer-type "nonNegativeInteger") (integer-type) ())

(defmethod initialize-instance :after ((type non-negative-integer-type) &key)
  (setf (min-inclusive type) (max* 0 (min-inclusive type))))


;;; unsignedLong

(defxsd (unsigned-long-type "unsignedLong") (non-negative-integer-type) ())

(defmethod initialize-instance :after ((type unsigned-long-type) &key)
  (setf (max-inclusive type) (min* 18446744073709551615 (max-inclusive type))))


;;; unsignedInt

(defxsd (unsigned-int-type "unsignedInt") (unsigned-long-type) ())

(defmethod initialize-instance :after ((type unsigned-int-type) &key)
  (setf (max-inclusive type) (min* 4294967295 (max-inclusive type))))


;;; unsignedShort

(defxsd (unsigned-short-type "unsignedShort") (unsigned-int-type) ())

(defmethod initialize-instance :after ((type unsigned-short-type) &key)
  (setf (max-inclusive type) (min* 65535 (max-inclusive type))))


;;; unsignedByte

(defxsd (unsigned-byte-type "unsignedByte") (unsigned-short-type) ())

(defmethod initialize-instance :after ((type unsigned-byte-type) &key)
  (setf (max-inclusive type) (min* 255 (max-inclusive type))))


;;; positiveInteger

(defxsd (positive-integer-type "positiveInteger") (non-negative-integer-type)
  ())

(defmethod initialize-instance :after ((type positive-integer-type) &key)
  (setf (min-inclusive type) (max* 1 (min-inclusive type))))