.iex.exs

import_if_available Ext.DateTime

datetime.ex

# lib/ext/datetime.ex

defmodule Ext.DateTime do
  defmacro sigil_Z(string, _) do
    quote do
      {:ok, datetime, 0} = DateTime.from_iso8601(unquote(string) <> "Z")
      datetime
    end
  end
end

old = Code.compiler_options.ignore_module_conflict
Code.compiler_options(ignore_module_conflict: true)

defimpl Inspect, for: DateTime do
  def inspect(%{calendar: Calendar.ISO, time_zone: "Etc/UTC"} = datetime, _) do
    string = DateTime.to_string(datetime) |> String.trim_trailing("Z")
    "~Z[" <> string <> "]"
  end

  def inspect(%{calendar: Calendar.ISO, year: year, month: month, day: day,
                hour: hour, minute: minute, second: second, microsecond: microsecond,
                time_zone: time_zone, zone_abbr: zone_abbr, utc_offset: utc_offset, std_offset: std_offset}, _) do
    "#DateTime<" <> Calendar.ISO.datetime_to_string(year, month, day, hour, minute, second, microsecond,
                                                    time_zone, zone_abbr, utc_offset, std_offset) <> ">"
  end

  def inspect(datetime, opts) do
    Inspect.Any.inspect(datetime, opts)
  end
end

Code.compiler_options(ignore_module_conflict: old)