anchor.diff:  (defvar *default-listprop* nil)
   (defvar *keyword-package* (find-package "KEYWORD"))
   (defvar *pointer-size* 4)
  +(defvar *assert* '*assert*)
  +(defvar *targets* '*targets*)
   
   (defvar *macros* nil)
   (defvar *builtins* (make-hash-table :test #'eq))
  
positive.code: (defun filter (fun x) (mapcar fun x))
  (defun make-hash-table (&key (test #'eql)) (%make-hash-table :test test))
  
  (%load "environment/env-load-cl.lisp")
  
negative.code:       *environment-path* *environment-filenames*
        *macroexpand-hook* *quasiquoteexpand-hook* *dotexpand-hook*
        *default-listprop* *keyword-package*
        *pointer-size*
        *assert* *targets*))
  
  ;;; Things we have to implement ourselves.
  (defconstant +implementations+
  