13.9.3 @expansion{} (→): Ÿ³«¤ò¼¨¤¹

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@lisp
(third '(a b c))
    @expansion{} (car (cdr (cdr '(a b c))))
    @result{} c
@end lisp

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(third '(a b c))
    → (car (cdr (cdr '(a b c))))
    ⇒ c

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