Provides the ruby-1.9 block form of Enumerator, where you can write:

   obj = Enumerator.new do |yielder|
      .. do stuff
      yielder.yield data      # or: yielder << data
      .. etc
   end

When obj.each is called, the block is run once. It should call yielder.yield with each item it wishes to generate.

Example:

  fib = Enumerator.new { |y|
    a = b = 1
    loop {
      y << a
      a, b = b, a + b
    }
  }

  assert_equal [1, 1, 2, 3, 5, 8, 13, 21, 34, 55], fib.take(10)

Convert an Enumerator object into a hash. This is equivalent to Array#to_h.

  e1 = [[1,:a],[2,:b],[3,:c]].to_enum
  e1.to_h #=> { 1=>:a, 2=>:b, 3=>:c }

  e2 = [1,2,3,4,5].to_enum
  e2.to_h  #=> {5=>nil, 1=>2, 3=>4}

  e3 = [1,2,1,3,1,5].to_enum
  e3.to_h #=> {1=>5}

CREDIT: Sandor Szücs

This is equivalent to Array#to_h_assoc.

This is equivalent to Array#to_h_auto.

This is equivalent to Array#to_h_flat.

This is equivalent to Array#to_h_multi.

This is equivalent to Array#to_h_splat.