我寫這樣一個Lisp函數:Lisp函數調用錯誤
(defun power (base exponent)
(if (= exponent 0)
1
(* base (power (- exponent 1)))))
當我嘗試調用它,但是,我得到了一些錯誤:
CL-USER 2 > (power 2 3)
Error: POWER got 1 arg, wanted at least 2.
1 (abort) Return to level 0.
2 Return to top loop level 0.
Type :b for backtrace or :c <option number> to proceed.
Type :bug-form "<subject>" for a bug report template or :? for other options.
CL-USER 3 : 1 > (power 2)
Error: POWER got 1 arg, wanted at least 2.
1 (abort) Return to level 1.
2 Return to debug level 1.
3 Return to level 0.
4 Return to top loop level 0.
Type :b for backtrace or :c <option number> to proceed.
Type :bug-form "<subject>" for a bug report template or :? for other options.
CL-USER 4 : 2 > (power 2 3 4)
Error: POWER got 3 args, wanted 2.
1 (continue) Ignore the extra arg.
2 (abort) Return to level 2.
3 Return to debug level 2.
4 Return to level 1.
5 Return to debug level 1.
6 Return to level 0.
7 Return to top loop level 0.
Type :b for backtrace or :c <option number> to proceed.
Type :bug-form "<subject>" for a bug report template or :? for other options.
這是怎麼回事?如果我給出兩個論點,它認爲我給了它一個。如果我給它三個,它認爲我給了它三個。如果我給它一個,它認爲我給它一個...