anchor.diff:    (+! (delayed-exprs) (frontend (list x)))
     nil)
   
  -(fn add-late-symbol (x)
  -  (= (href (late-symbols) x) t)
  -  x)
  -
   (fn add-toplevel-expression (x)
     (push x (accumulated-toplevel-expressions)))
   
  
positive.code: 
          :symbol-translations      (copy-list symbol-translations)
          :defined-classes          (copy-hash-table defined-classes)
          :late-symbols             (copy-hash-table late-symbols)
          :exported-closures        (copy-list exported-closures)
          :delayed-exprs            (copy-list delayed-exprs)
          :memorized-sources        (copy-list memorized-sources)
  
negative.code: (transpiler-getter-not-global function-body      (cdr (transpiler-defined-function tr x)))
  (transpiler-getter wanted-function?        (href (transpiler-wanted-functions-hash tr) x))
  (transpiler-getter wanted-variable?        (href (transpiler-wanted-variables-hash tr) x))
  
  (transpiler-getter add-defined-variable  (= (href (transpiler-defined-variables tr) x) t)
                                           x)
  