anchor.diff:       :for code :from (ascii-code #\0) :to (ascii-code #\9)
        :for n :from 0
        :do (assert (eql n (code-ascii-digit-p code))))
  -  (string= (ascii-string #(65 66 67 68)) "abcd")
  -  (bytes=  #(65 66 67 68)  (ascii-bytes "abcd"))
  +  (assert (typep (nth-value 1 (ignore-errors (ascii-string #(65 66 8 67 69)))) 'decoding-error))
  +  (assert (typep (nth-value 1 (ignore-errors (ascii-bytes "En été, il fait chaud."))) 'encoding-error))
  +  (assert (string= "ABCD" (ascii-string #(65 66 67 68))))
  +  (assert (string= "ABCD" (ascii-string #(0 0 65 66 67 68 0 0 0 0) :start 2 :end 6)))
  +  (assert (bytes=  #(65 66 67 68)  (ascii-bytes "ABCD")))
  +  (assert (bytes=  #(65 66 67 68)  (ascii-bytes "00ABCD0000" :start 2 :end 6)))
     (let ((*readtable* (copy-readtable nil)))
       (set-dispatch-macro-character #\# #\Y (function ascii-dispatch-macro)
                                     *readtable*)
  
positive.code:   :success)
  
  
  ;;;; THE END ;;;;
  
negative.code: (declaim (inline ascii-printable-code-p))
  (defun ascii-printable-code-p (code)
    "RETURN:  Whether CODE is the code of an ASCII printable character."
    (<= sp code (1- del)))
  
  
  (declaim (inline ascii-control-code-p))
  (defun ascii-control-code-p (code)
    "RETURN:  Whether CODE is an ASCII control code."
    (or (<= nul code (1- sp)) (= del code)))
  
  
  
  