anchor.diff:  
   (defun expression-expand (x)
     (with-transpiler-expex
  -    (with-temporary (expex-warnings? *expex*) nil
  -      (expression-expand-0 x))))
  +    (expression-expand-0 x)))
   
   (defun fake-expression-expand (x)
     (with-transpiler-expex
  
positive.code:   (aprog1 (expex-sym)
      (funinfo-var-add *funinfo* !)))
  
  (defun expex-warn (x)
    (& (expex-warnings? *expex*)
       (symbol? x)
       (not (eq '~%cont x)
            (eq '~%this x)
            (transpiler-defined-symbol? *funinfo* x)
            (can-import-function? *transpiler* x))
       (error "Symbol ~A is not defined in ~A."
              (symbol-name x)
              (human-readable-funinfo-names *funinfo*))))
  
  
  ;;;; PREDICATES
  
  
negative.code: 		  x))
  
  (defun expex-argexpand-0 (fun args)
    (let argdef (| (funinfo-get-local-function-args *funinfo* fun)
                   (current-transpiler-function-arguments fun))
      (transpiler-expand-literal-characters
  