Practicing Elixir or any programming language

Re:Practicing Elixir or any programming language by hokiewv on Friday August 25, 2017 @09:33AM (#15098260)

I agree though one thing I would caution is it is good practice to always return the same type from a function even though it is an untyped language. The whole thing can be boiled down even more if pattern matching is used in parsing the initial string.

  def convert(<<h::bytes-size(2)>> <> ":" <>
              <<m::bytes-size(2)>> <> ":" <>
              <<s::bytes-size(2)>> <> <<period::bytes-size(2)>>) do
   "#{formatted_hour(h,period)}:#{m}:#{s}"
  end

  defp formatted_hour(hours,"PM"), do: "#{String.to_integer(hours) + 12}"
  defp formatted_hour("12","AM"), do: "00"
  defp formatted_hour(hours, "AM"), do: hours

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Re:Practicing Elixir or any programming language by midgetjones on Friday August 25, 2017 @09:58AM (#15098428)

Good point! If you're going to pattern match in the initial string then who even needs the second function?

    def convert("12:" <> <<m::bytes-size(2)>> <> ":" <> <<s::bytes-size(2)>> <> "AM") do
      "00:#{m}:#{s}"
    end

    def convert(<<h::bytes-size(2)>> <> ":" <> <<m::bytes-size(2)>> <> ":" <> <<s::bytes-size(2)>> <> "PM") do
      h = 12 + String.to_integer(h)
      "#{h}:#{m}:#{s}"
    end

    def convert(<<h::bytes-size(2)>> <> ":" <> <<m::bytes-size(2)>> <> ":" <> <<s::bytes-size(2)>> <> "AM") do
      "#{h}:#{m}:#{s}"
    end

Whether that's an improvement or not is another matter :)

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Re:Practicing Elixir or any programming language by ericdouglas on Saturday August 26, 2017 @08:59AM (#15105238)

Crazy stuff! :D

I'm wondering how our future-self would feel about such cleverness haha

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Re:Practicing Elixir or any programming language by ericdouglas on Saturday August 26, 2017 @08:18AM (#15105131)

I really liked this:

    "#{String.to_integer(hours) + 12}"

Used it now refactoring the code, many thanks for your suggestion!

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