anchor.diff:  ;;;; Copyright (c) 2005-2006,2008-2009 Sven Klose <pixel@copei.de>
   ;;;;
   ;;;; Generalized hash-table
  +
  +(defvar *default-hash-size* 2048)
   
   (defstruct %hash-table
     test              ; Function for equality test of keys.
  
positive.code: 				      b))))
  
  (defun hashkeys (h)
    (with (keys nil)
  	(dotimes (i (length (%hash-table-hash h)) keys)
  	  (setf keys (append (carlist (aref (%hash-table-hash h) i)) keys)))))
  
negative.code: (defun make-hash-table (&key test size rehash-size rehash-threshold)
    "Create a new hash table."
    (make-%hash-table
      :test (or test #'eq) :size *default-hash-size*
      :rehash-size rehash-size :rehash-threshold rehash-threshold
      :hash (make-array *default-hash-size*)))
  
  (defun %make-hash-index-num (h k)
    "Make hash index from number."
  