defmodule Createproj do
  @moduledoc """
  Documentation for `Createproj`.
  """
  def print_help do
    IO.puts(
      "Usage: newP" <>
        " -f filepath: creates a new project\n" <>
        "-b: adds boilerplate\n"
    )
  end

  def write_boilerplate(project_name) do
    file_name = project_name <> ".ex"
    file_path = Path.join([project_name, file_name])
    boilerplate = "defmodule #{project_name} do\nend"
    File.write(file_path, boilerplate, [:append])
  end

  def get_filename(args) do
    Enum.with_index(args)
    |> Enum.find(fn {arg, index} -> arg == "-f" and index < length(args) - 1 end)
    |> case do
      {_, index} ->
        Enum.at(args, index + 1)

      {nil} ->
        nil
    end
  end

  def create_folder(project_name, file_name \\ "") do
    folder_path = Path.join([project_name, file_name])

    File.mkdir(folder_path)
    |> case do
      :ok -> IO.puts("created#{folder_path}")
      {_, _} -> IO.puts("failed to make #{file_name}")
    end
  end

  def main(args) do
    IO.inspect(args)
    new_file = Enum.member?(args, "-f")
    boilerplate = Enum.member?(args, "-b")

    cond do
      new_file and not boilerplate ->
        project_name = get_filename(args)
        create_folder(project_name)
        create_folder(project_name, "/lib")
        create_folder(project_name, "/test")

      new_file and boilerplate ->
        project_name = get_filename(args)
        create_folder(project_name)
        create_folder(project_name, "/lib")
        create_folder(project_name, "/test")
        write_boilerplate(project_name)

      true ->
        print_help()
    end
  end
end

compilation works great but when I run:

~/projects ./createproj -f dio -b
** (MatchError) no match of right hand side value: "dio"
    (createproj 0.1.0) lib/createproj.ex:33: Createproj.main/1
    (elixir 1.18.1) lib/kernel/cli.ex:137: anonymous fn/3 in Kernel.CLI.exec_fun/2

If I run it from the iex like this:

Createproj.main(["-f", "cane", "-b"])
["-f", "cane", "-b"]
createdcane
createdcane/lib
createdcane/test
:ok

as you can see everything works… any idea what’s going on?