anchor.diff:  (in-package :cldm)
   
  -(unless *load-truename*
  -  (error "This file must be LOADed to set up CLDM."))
  -
  -(defvar *cldm-home*
  -  (make-pathname :name nil :type nil
  -                 :defaults *load-truename*))
  +;; (unless *load-truename*
  +;;   (error "This file must be LOADed to set up CLDM."))
  +
  +;; (defvar *cldm-home*
  +;;   (make-pathname :name nil :type nil
  +;;                  :defaults *load-truename*))
   
   (defparameter *cld-libraries* (make-hash-table :test #'equalp))
   
  -(defun find-cld-library (name)
  -  (gethash name *cld-libraries*))
  +(defun find-cld-library (name &optional (error-p t))
  +  (or (gethash name *cld-libraries*)
  +      (when error-p
  +	(error "Library ~A not found" name))))
   
   (defun list-cld-libraries ()
     (loop for library being the hash-values of *cld-libraries*
  
positive.code:      `(make-instance 'url-repository-address
  		     :url ,(second address)))
      (t (error "Invalid repository ~A" address))))
  
negative.code: 
  (defun register-cld-library (library)
    (setf (gethash (library-name library) *cld-libraries*) library))
  
  (defun find-cld-library-version (library version &optional (error-p t))
    (loop for version in (library-versions library)
         when (equalp (version version) version)
         do (return-from find-cld-library-version version))
    (when error-p
      (error "~A version ~A not found" library version)))
  
  (defclass cld-library ()
    ((name :initarg :name
  