apply 将参数表传给指定的函数

mccad

将参数表传给指定的函数

(apply ’function list)

参数

’function

函数，可以是表示 defun 或 lambda 表达式的符号。

list

表。如果函数不接收参数，则该参数为 nil。

返回值

函数调用的结果。

示例

命令: (apply '+ '(1 2 3))

6

命令: (apply 'strcat '("a" "b" "c"))

"abc"

mccad

示例预留

【KAIXIN】

;画一条直线
(defun c:XX()
    (setq a '("line" (0 0) (100 100) ""))
    (apply 'command a)
)

Throne

1. ;求点表中心
   
2. (defun avg_pts (lst / n)
   
3.   (setq n (float (length lst)))
   
4.   (mapcar '/ (apply 'mapcar (cons '+ lst)) (list n n n))
   
5. )
   
6. 
   
7. (defun avg_pts2        (lst / n)
   
8.   (setq n (float (length lst)))
   
9.   (mapcar (function (lambda (x) (/ x n)))
   
10.           (apply 'mapcar (cons '+ lst))
    
11.   )
    
12. )

;求点表中心<br /> (defun avg_pts (lst / n)<br />   (setq n (float (length lst)))<br />   (mapcar '/ (apply 'mapcar (cons '+ lst)) (list n n n))<br /> )<br /> <br /> (defun avg_pts2        (lst / n)<br />   (setq n (float (length lst)))<br />   (mapcar (function (lambda (x) (/ x n)))<br />           (apply 'mapcar (cons '+ lst))<br />   )<br /> )

Throne

2. ;;从点列表(point list)得到坐标范围(coordinate extents).
   
3. (defun GetExtents (plist /)
   
4.   (list
   
5.     (apply 'mapcar (cons 'min plist))
   
6.     (apply 'mapcar (cons 'max plist))
   
7.   )
   
8. )

;;从点列表(point list)得到坐标范围(coordinate extents).<br /> (defun GetExtents (plist /)<br />   (list<br />     (apply 'mapcar (cons 'min plist))<br />     (apply 'mapcar (cons 'max plist))<br />   )<br /> )

Throne

;; if you only want the X and Y values
(setq p (apply '(lambda (x y z)(list x y))(getpoint "\nPick a point: ")))

;; if you want to reverse the X and Y values
(setq p (apply '(lambda (x y z)(list y x))(getpoint "\nPick a point: ")))