11.4 ´Ø¿ô¤òÄêµÁ¤¹¤ë

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Special Form: defun name argument-list body-forms

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(lambda argument-list . body-forms)

defun¤Ï¡¢¤³¤Î¥é¥à¥À¼°¤òname¤Î´Ø¿ô¥»¥ë¤Ë³ÊǼ¤¹¤ë¡£ ÃÍname¤òÊÖ¤¹¤¬¡¢ÉáÄÌ¡¢¤³¤ì¤Ï̵»ë¤¹¤ë¡£

Á°½Ò¡Êsee Lambda Expressions¡Ë¤Î¤è¤¦¤Ë¡¢ argument-list¤Ï°ú¿ô̾¤Î¥ê¥¹¥È¤Ç¤¢¤ê¡¢ ¥­¡¼¥ï¡¼¥É&optional¤ä&rest¤¬Æþ¤Ã¤Æ¤¤¤Æ¤â¤è¤¤¡£ ¤Þ¤¿¡¢body-forms¤ÎºÇ½é¤Î2¤Ä¤Ï¡¢ÀâÌÀʸ»úÎó¤ÈÂÐÏÃÀë¸À¤Ç¤â¤è¤¤¡£

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(defun foo () 5)
     ⇒ foo

(foo)
     ⇒ 5

(defun bar (a &optional b &rest c)
    (list a b c))
     ⇒ bar

(bar 1 2 3 4 5)
     ⇒ (1 2 (3 4 5))

(bar 1)
     ⇒ (1 nil nil)

(bar)
error→ Wrong number of arguments.

(defun capitalize-backwards ()
  "Upcase the last letter of a word."
  (interactive)
  (backward-word 1)
  (forward-word 1)
  (backward-char 1)
  (capitalize-word 1))
     ⇒ capitalize-backwards

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Function: defalias name definition

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