lisp

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have this macro, which rewrites define. If I remove the " ` " backtick it won't work. What is the explanation? (defmacro define ((name &rest r) body) `(defun ,name ,r ,body)) 回答1: A single quote followed by the written representation of a value will produce that value: Example: '(1 x "foo") will produce a value that prints as (1 x "foo") . Suppose now that I don't want a literal symbol x in the list. I have a variable x in my program, and I want to insert the value to which x . To mark that I want the value of x rather than the symbol x ,

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: If I have a list like this ((0 1 2) (3 4 5) (6 7 8) (0 3 6) (1 3 7) (2 4 8) (0 4 8) (2 4 6)) And I want to find the index of (0 3 6) , is there a built-in function to do this? POSITION doesn't seem to work when the search item is itself a list. 回答1: See hyperspec . POSITION can take a :test argument: (position '(0 3 6) '((0 1 2) (3 4 5) (6 7 8) (0 3 6) (1 3 7) (2 4 8) (0 4 8) (2 4 6)) :test #'equal)) 3 The default test for POSITION (and other sequence operations) is EQL, by the way. 文章来源: Get index of list within list in Lisp

What is the Emacs mode or package that highlights Lisp forms changing the color of the backgrounds so that the form you are in has one color, the outer form another, the outer outer form another and so on? fincomus You may want to try mwe-color-box (screenshot below) or read Five approaches to s-expression highlighting by Lemondor . (source: foldr.org ) Take a look at screenshots here http://lemonodor.com/archives/001207.html , may be that is what you want. I don't use it, but this might be what you're looking for: http://www.emacswiki.org/emacs/RainbowDelimiters 来源： https://stackoverflow.com

If we define a function something like (defun foo(x) (setf x somevalue)) Is x defined as a local variable or global? using setf/q is setting the value to be global. if it is global can anyone tell me how to define a local variable in lisp other than let ? Thanks! Consider the following example (let ((x 0)) (defun foo (y) (when (equal x 0) (setq x y)) (when (< x y) (setq x y)) x)) when I am giving some input to foo like (foo 2) , it is returning 2 and if we execute the function again with (foo 1) it still returns 2 and (foo 3) returns 3.This is what i actually want it do.But the question is how