Ruby: Creating iterators

iterators.rb

def my_each(array)
  i = 0
  while i < array.length
    yield(array[i])
    i+=1
  end 
  array
end


def my_collect(array)
  i = 0
  collect = []
  while i < array.length
    collect << (yield(array[i]))
    i+=1
  end 
  collect
end

def my_select(array)
  i = 0
  select = []
  while i < array.length
    if (yield(array[i]))
      select << array[i]
    end
    i+=1
  end 
  select
end

def my_none?(array)
  i = 0
  while i < array.length
    if (yield(array[i]))
      return false
    end
    i += 1
  end
  true
end

array = [1,2,3]

my_none?(array) do |i|
  i.is_a?(String)
end