gen_list.ex

def gen_list() do
  gen_list([])
end

# Empty list. Adding first element
defp gen_list([]) do
  gen_list([ gen_number | [] ])
end
# When list is non-empty and has less than 7 elements
defp gen_list(list) when length(list) < 7 do
  n = gen_number
  # Should make sure that no dublicates are created
  if Enum.member?(list, n), do: gen_list(list)
  gen_list( [gen_number | list] )
end
# Return list when 7 elements are in the list
defp gen_list(list) when length(list) == 7 do
  list
end

#Generate a random number in the range 1 to 36
defp gen_number() do
  :random.uniform(36)
end