anchor.diff:  	  (common-address-path common-address)))
   
   (defun url-scheme (url)
  -  "Get scheme for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-scheme} returns a _keyword_ denoting the scheme part of _url_."
     (url-scheme% (url url)))
   
   (defun url-address (url)
  -  "Get address for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-address} returns a _string_ denoting the address part of _url_."
     (let ((url (url url)))
       (if (common-address-p #1=(url-address% url))
           (common-address-string #1#)
           #1#)))
   
   (defun url-user (url)
  -  "Get user for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-user} returns a _string_ denoting the user part of _url_."
     (let ((url (url url)))
       (when (common-address-p #1=(url-address% url))
         (common-address-user #1#))))
   
   (defun url-password (url)
  -  "Get password for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-password} returns a _string_ denoting the password part of
  +   _url_."
     (let ((url (url url)))
       (when (common-address-p #1=(url-address% url))
         (common-address-password #1#))))
   
   (defun url-host (url)
  -  "Get host for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-host} returns a _string_ denoting the host part of _url_."
     (let ((url (url url)))
       (when (common-address-p #1=(url-address% url))
         (common-address-host #1#))))
   
   (defun url-port (url)
  -  "Get port for URL."
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-port} returns a non-negative _integer_ denoting the port part of
  +   _url_."
     (let ((url (url url)))
       (when (common-address-p #1=(url-address% url))
         (common-address-port #1#))))
   
   (defun url-path (url)
  +  "*Arguments and Values:*
  +
  +   _url_—a _url_ designator.
  +
  +   *Description*:
  +
  +   {url-path} returns a _string_ denoting the path part of _url_."
     "Get path for URL."
     (let ((url (url url)))
       (when (common-address-p #1=(url-address% url))
  
positive.code:    (encode-pathname (translate-logical-pathname path))))
  
  (defun make-url (scheme &key address user password host port path)
    "Make URL for SCHEME and ADDRESS or SCHEME and USER, PASSWORD, HOST,
    PORT and PATH."
    (if address
        (make-url% :scheme% scheme :address% address)
        (make-url% :scheme% scheme
  
negative.code:   (:documentation "Condition signaling a malformed URL string."))
  
  (defun url-encode (string)
    "*Arguments and Values:*
  
     _string_—a _string.
  
     *Description*:
  
     {url-encode} encodes _string_ using _Percent-Encoding_¹.
  
     *See Also:*
  
     + 1. [Percent-Encoding](http://tools.ietf.org/html/rfc3986#section-2.1)"
    (encode string :test 'unreservedp :www-form nil :encoding :utf-8))
  
  (defun url-decode (string)
    "*Arguments and Values:*
  
     _string_—a _string.
  
     *Description*:
  
     {url-decode} decodes encoded _string_ using _Percent-Encoding_¹.
  
     *See Also:*
  
     + 1. [Percent-Encoding](http://tools.ietf.org/html/rfc3986#section-2.1)"
    (decode string :www-form nil :encoding :utf-8))
  
  (defun encode-pathname (path)
  