# Simple Example ```elixir Mix.install([ {:prompt, "~> 0.9.3"} ]) ``` ## Starting Out Lets go through an example of creating and building a new commandline/terminal app with `Prompt` that will acknowledge a person. Lets call it `ack`. <!-- livebook:{"break_markdown":true} --> Lets define a `CLI` module and create where we can define what arguments we allow and what options are available for our tool. ```elixir defmodule CLI do @moduledoc """ DOCUMENTATION FOR THE TOOL """ use Prompt.Router, otp_app: :ack command :hello, HelloCommand do arg(:help, :boolean) end end ``` ## Now Create the Command Handler Now we'll have to create the handler for the `hello` command. ```elixir defmodule HelloCommand do @moduledoc """ The help message ack hello <name> --help prints this help message """ use Prompt.Command @impl true def init(opts) do # opts is map of data which includes the # options for the command and any other data passed in # Our opts here look like give the following incanatation `ack hello bob`: # `%{help: false, leftover: ["bob"]} # `init/1` can be used to transform any arguments if needed. Map.put(opts, :name, List.first(opts.leftover, nil)) end @impl true def process(%{help: true}), do: help() def process(%{name: name}) do display("Hello #{name}", color: :green) end end ``` ## Simulate calling the CLI ```elixir CLI.main(["hello", "bob"]) ``` ```elixir CLI.main(["hello", "--help"]) ``` ## Bundle and Distribute To build your app, you'll need to decide if you want an escript or a binary. The former will require the user of your tool to have Elixir and Erlang installed on their system. A binary built using Bakeware or Burrito can be distributed and used without having Elixir or Erlang on the system. See the [documentation](https://hexdocs.pm/prompt/Prompt.html#module-building-for-distribution) for details on both