非破坏性子序列,lisp中除外
我知道lisp中的subseq返回一个范围内的子序列。除了该范围之外,是否有任何东西会返回子序列,并且应该是非破坏性的?非常感谢您的帮助。您就不能:非破坏性子序列,lisp中除外,lisp,common-lisp,subsequence,Lisp,Common Lisp,Subsequence,我知道lisp中的subseq返回一个范围内的子序列。除了该范围之外,是否有任何东西会返回子序列,并且应该是非破坏性的?非常感谢您的帮助。您就不能: (defun seq-drop-subseq (SEQ START &optional END) (if END (nconc (seq-take START) (seq-drop END)) (seq-take START))) 编辑:我得去看看删除就可以了。你就不能: (defun seq-drop-subse
(defun seq-drop-subseq (SEQ START &optional END)
(if END
(nconc (seq-take START) (seq-drop END))
(seq-take START)))
编辑:我得去看看<代码>删除就可以了。你就不能:
(defun seq-drop-subseq (SEQ START &optional END)
(if END
(nconc (seq-take START) (seq-drop END))
(seq-take START)))
编辑:我得去看看<代码>删除执行此操作。您可以使用
串联
和子序列
对任何序列执行此操作:
(defun sequence-except (sequence start end)
(concatenate (sequence-type sequence)
(subseq sequence 0 start)
(subseq sequence end)))
以下内容足以确定位向量、字符串等的输入序列类型:
(defun sequence-type (sequence)
(etypecase sequence
(list 'list)
(array `(array ,(array-element-type sequence) (*)))))
测试:
(loop for test in (list
#*10101001
"abcd"
'(0 3 2)
nil
#(1 2 3 4)
(make-array 4
:adjustable t
:fill-pointer T
:initial-contents
'(a b c d)))
collect (concatenate (sequence-type test) test))
您可以使用
串联
和子序列
对任何序列执行此操作:
(defun sequence-except (sequence start end)
(concatenate (sequence-type sequence)
(subseq sequence 0 start)
(subseq sequence end)))
以下内容足以确定位向量、字符串等的输入序列类型:
(defun sequence-type (sequence)
(etypecase sequence
(list 'list)
(array `(array ,(array-element-type sequence) (*)))))
测试:
(loop for test in (list
#*10101001
"abcd"
'(0 3 2)
nil
#(1 2 3 4)
(make-array 4
:adjustable t
:fill-pointer T
:initial-contents
'(a b c d)))
collect (concatenate (sequence-type test) test))
没有内置的东西。获取范围前的子序列和范围后的子序列,然后将它们与
ncoc
连接起来。没有任何内置内容。获取范围前的子序列和范围后的子序列,然后使用ncoc
将它们连接起来。