下一个元素是(current+1)或0 (ruby)

I have an interval let's say (0..3) where next element is +1 unless the last. Then the next is 0. I solved it by the code below. Just wondering if there is anything else outhere :-)

我有一个区间(0.. .3)下一个元素是+1除非是最后一个元素。然后下一个是0。我用下面的代码解决了这个问题。我想知道还有什么其他的吗?

def next(max,current)

if current+1 == max
  return 0
else
  return current+1
end  
end

EDIT

please note that when the code runs I need to be able to assign any 'valid number' in my example 0..3 at any time.

请注意，当代码运行时，我需要能够在示例0中分配任何“有效数字”。3在任何时间。

2 个解决方案

#1

Ruby 1.8.7 has Enumerable#cycle

Ruby 1.8.7可列举的#循环

(0..3).cycle{|x| puts x}

will cycle forever.

永远循环。

I think this is really cool:

我觉得这真的很酷:

looper = (0..3).cycle
20.times { puts looper.next }

#2

How about:

如何:

def next(max,current)
(current+1) % max
end

Should work unless max==0, but you could easily catch that and bail. :)

应该是有效的，除非max= 0，但你可以很容易地抓住它并保释。:)

Happy coding!

编码快乐!

Edit: You should also be aware that next is a reserved keyword (see this overview), it'd be wise to choose another name for your method..

编辑:你也应该知道next是一个保留的关键字(见这个概述)，为你的方法选择另一个名字是明智的。

#1