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About an example in Emacs Lisp manual

From: Xue Fuqiao
Subject: About an example in Emacs Lisp manual
Date: Sun, 10 Feb 2013 22:19:25 +0800

In (info "(elisp) Translation Keymaps"):

    For example, here's how to define `C-c h' to turn the character that
  follows into a Hyper character:
     (defun hyperify (prompt)
       (let ((e (read-event)))
         (vector (if (numberp e)
                     (logior (lsh 1 24) e)
                   (if (memq 'hyper (event-modifiers e))
                     (add-event-modifier "H-" e))))))
     (defun add-event-modifier (string e)
       (let ((symbol (if (symbolp e) e (car e))))
         (setq symbol (intern (concat string
                                      (symbol-name symbol))))
         (if (symbolp e)
           (cons symbol (cdr e)))))
     (define-key local-function-key-map "\C-ch" 'hyperify)

In the first `defun' form, if `e' is a number, (vector (logior (lsh 1 24) e)) 
will be returned.  I don't understand what the meaning of the bitwise-or and 
bit-shifting functions are here.  Can anybody explain it for me (and maybe for 
other people)?  Thanks.

Best regards, Xue Fuqiao.

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