Recommended way to add ordinal suffix for the day of month?

[najicham]

I cannot find the ordinal suffix for the month in the Timex.Format.DateTime.Formatter module. Similar to what PHP has for their datetime:
English ordinal suffix for the day of the month, 2 characters | st, nd, rd or th.
http://php.net/manual/en/function.date.php

Is a custom formatter recommended to add the suffix?

[najicham]

For now I created this module to get the suffix and then I put the result in the Timex.format call.

defmodule OrdinalSuffix do
  def get(i) do
    value = elem(Integer.parse(i), 0)
    j = div(value, 10)
    k = div(value, 100)

    cond do
      j == 1 && k != 11 ->
        "st"
      j == 2 && k != 12 ->
        "nd"
      j == 3 && k != 13 ->
        "rd"
      true ->
        "th"
    end
  end
end

I call it with this:

sample_date = {2016,3,4}
month = Timex.format(sample_date, "{D}")
suffix = OrdinalSuffix.get(elem(month, 1))
Timex.format(sample_date, "{YYYY}-{0M}-{D}" <> suffix)

[bitwalker]

I'm open to extending the formatter with a new token, if you would like to submit a PR!