anchor.diff:  ;;;
   ;;; Class SINGLE-FLOAT-LESS-AST.
   ;;;
  -;;; This class can be used to implement a binary LESS-THAN function.
  -;;; It requires both its arguments to be of type SINGLE-FLOAT.  It can
  +;;; This class can be used to implement a binary < function.  It
  +;;; requires both its arguments to be of type SINGLE-FLOAT.  It can
   ;;; only occur as the TEST-AST of an IF-AST.  If this AST occurs in a
   ;;; position where a value is required, an error is signaled.
   ;;;
  
positive.code: ;;;
  ;;; Class DOUBLE-FLOAT-LESS-AST.
  ;;;
  ;;; This class can be used to implement a binary LESS-THAN function.
  ;;; It requires both its arguments to be of type DOUBLE-FLOAT.  It can
  ;;; only occur as the TEST-AST of an IF-AST.  If this AST occurs in a
  ;;; position where a value is required, an error is signaled.
  ;;;
  
negative.code: ;;;
  ;;; Class LONG-FLOAT-LESS-AST.
  ;;;
  ;;; This class can be used to implement a binary < function.  It
  ;;; requires both its arguments to be of type LONG-FLOAT.  It can only
  ;;; occur as the TEST-AST of an IF-AST.  If this AST occurs in a
  ;;; position where a value is required, an error is signaled.
  ;;;
  ;;; It can be used by an implementation that supports the LONG-FLOAT
  