(module alias mzscheme
  ;; Practice writing macros that themselves generate macros.  
  
  (provide alias)
  
  ;; (alias old-keyword new-keyword)   SYNTAX
  ;; Creates a new syntax for new-keyword; any occurrence of new-keyword
  ;; is replaced with the old-keyword.
  (define-syntax (alias stx-1)
    (syntax-case stx-1 ()
      [(_1 orig new)
       (syntax/loc stx-1
         (define-syntax (new stx-2)
           (syntax-case stx-2 ()
             [_2
              (identifier? stx-2)
              (syntax/loc stx-2
                orig)]
             [(_2 e (... ...))
              (syntax/loc stx-2
                (orig e (... ...)))])))])))