anchor.diff:          ; Write a pointer to the current line
           (with (pointer
             (cond
  -            ((! range) "^")
  -            ((and (.> position :finish) (= (.> position :start :line) (.> position :finish :line)))
  -              (string/rep "^" (succ (- (.> position :finish :column) (.> position :start :column)))))
  -            (true "^...")))
  +            [(! range) "^"]
  +            [(and (.> position :finish) (= (.> position :start :line) (.> position :finish :line)))
  +             (string/rep "^" (succ (- (.> position :finish :column) (.> position :start :column))))]
  +            [true "^..."]))
   
             (print! (string/format code "" (string/..
               (string/rep " " (- (.> position :start :column) 1))
  
positive.code:     (while node
        (with (formatted (format-node node))
          (cond
            ((= previous nil) (print! (colored 96 (string/.. "  => " formatted))))
            ((/= previous formatted) (print! (string/.. "  in " formatted)))
            (true nil))
  
          (set! previous formatted)
          (set! node (.> node :parent))))))
  
negative.code: 
     This is either its position in a source file or the macro which created it"
    (cond
      [(and (.> node :range) (.> node :contents))
       (string/format "%s (%q)" (format-range (.> node :range)) (.> node :contents))]
      [(.> node :range) (format-range (.> node :range))]
      [(.> node :macro)
       (with (macro (.> node :macro))
         (string/format "macro expansion of %s (%s)"
                        (.> macro :var :name)
                        (format-node (.> macro :node))))]
      [(and (.> node :start) (.> node :finish))
       (format-range node)]
      [true "?"]))
  
  (defun get-source (node)
    "Get the nearest source position of NODE
  