Elixir: create an armored sha256 hash of an input

hash_signature.ex

defmodule HashSignature do
  @doc """
    encode input to a sha256 and output as an armored string.
    results should be fully portable and consistent with other
    tools.
  """
  def get( input ) do
    :crypto.hash( :sha256, input )
    |> :crypto.bytes_to_integer
    |> (fn i -> :io_lib.format("~64.16.0b",[i]) |> hd end ).()
    |> to_string
  end
end