anchor.diff:  
   ;;; The following standardized atomic types are conditions, so they
   ;;; are subclasses of the class CONDITION.  None of them takes any
  -;;; arguments, so they can only be used as atomic type specifiers. 
  +;;; arguments, so they can only be used as atomic type specifiers.
   ;;;
   ;;; arithmetic-error, simple-condition, simple-error,
   ;;; simple-type-error, simple-warning, cell-error, storage-condition,
  
positive.code: ;;; simple-vector.  Nothing is of type nil.  We are left with:
  ;;; compiled-function, short-float, single-float, double-float,
  ;;; long-float, simple-array.
  ;;; 
  ;;; 
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  ;;;
  
negative.code: ;;; is a character.  The other character types can be defined using
  ;;; this predicate and SATISFIES with a functions that check the range
  ;;; of the character code or by using a bitmap.
  ;;;
  ;;; Stream types: stream, broadcast-stream, concatenated-stream,
  ;;; string-stream, echo-stream, synonym-stream, two-way-stream,
  ;;; file-stream.
  