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rubyenumerator

Ruby: Loop back Enumerator

Is there a way to loop back an enumerator in Ruby? Given this piece of code:

a=[1,2,3]
a.to_enum

a.next => 1
a.next => 2
a.next => 3
a.next => 1

How can I make the next method go back to the first element when the enumerator reached the last element?

Solution

  • You can use Enumerable#cycle:

    a = [1, 2, 3]
enum = a.cycle  #=> #<Enumerator: [1, 2, 3]:cycle>

enum.next       #=> 1
enum.next       #=> 2
enum.next       #=> 3
enum.next       #=> 1