使用可以有条件地使用下一个

before = 0
"0;1;2;3".split(";").each.with_index do |now, i|
    next if i < 1
    puts "before it was #{before}, now it is #{now}"
    before = now
end

输出:

before it was 0, now it is 1
before it was 1, now it is 2
before it was 2, now it is 3

我想它叫next。

在for-loops和迭代器方法中，例如each和map the next关键字，在ruby中具有跳转到循环的下一次迭代的效果(与C中的continue相同)。

然而，它实际上所做的只是从当前块返回。所以你可以将它用于任何需要块的方法——即使它与迭代无关。

next

另外，看看重做当前迭代的redo。

使用可以有条件地使用下一个

before = 0
"0;1;2;3".split(";").each.with_index do |now, i|
    next if i < 1
    puts "before it was #{before}, now it is #{now}"
    before = now
end

输出:

before it was 0, now it is 1
before it was 1, now it is 2
before it was 2, now it is 3

用一种更地道的方式来写伊恩·伯顿的回答:

(1..5).each do |x|
  next if x < 2
  puts x
end

打印:

  2
  3
  4
  5