anchor.diff:  (define-class scheme ()
     ((name (error "Scheme must have a name/scheme")
            :documentation "Scheme/name of the internal scheme.
  -E.g. \"gopher\", \"irc\".")
  +For instance, \"gopher\", \"irc\".")
      (callback
       nil
       :type (or null (function (url-designator buffer) t))
  
positive.code:   (:export-class-name-p t)
    (:export-accessor-names-p t)
    (:accessor-name-transformer (class*:make-name-transformer name))
    (:documentation "Representation of Nyxt-specific internal scheme."))
  
  (defvar *internal-schemes*
    (make-hash-table :test 'equal)
  
negative.code:   (typep object '(and sequence (not string))))
  
  (defun scalar-p (object)
    ;; REVIEW: List direct T subclasses instead?
    "Return true if OBJECT is of one of the following types:
  - symbol,
  - character,
  - string,
  