在Ruby中滚动数组-RolloveronarrayinRuby

2  

This would work:

这可行:

arr = [1,2,3,4,5]
arr[6 % arr.size] #=> 2

1  

Yes, it is possible to patch Array class in such way:

是的,有可能以这种方式修补Array类:

module RollOver
  def [](index)
    super index % size
  end
end

Array.class_eval do
  prepend RollOver
end

array = [1, 2, 3, 4, 5]
puts array[6] # => 2

But it is NOT recommended. Imagine how much code could be broken because of this patch. You better define another method for such operation.

但不建议这样做。想象一下,由于这个补丁,可能会破坏多少代码。您最好为此类操作定义另一种方法。

UPDATE

If this behaviour is needed for one particular array only, then the best solution is:

如果仅对一个特定阵列需要此行为,那么最佳解决方案是:

array = [1, 2, 3, 4, 5]

def array.[](index)
  super index % size
end

puts array[6] # => 2

Yes, Ruby allows that :-)

是的,Ruby允许:-)