# Hello World Greet the user by name, or by saying "Hello, World!" if no name is given. ["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is the traditional first program for beginning programming in a new language. **Note:** You can skip this exercise by running: exercism skip $TRACK_ID hello-world ## Specification Write a `Hello World!` function that can greet someone given their name. The function should return the appropriate greeting. For an input of "Alice", the response should be "Hello, Alice!". If a name is not given, the response should be "Hello, World!" ## Test-Driven Development As programmers mature, they eventually want to test their code. Here at Exercism we simulate [Test-Driven Development](http://en.wikipedia.org/wiki/Test-driven_development) (TDD), where you write your tests before writing any functionality. The simulation comes in the form of a pre-written test suite, which will signal that you have solved the problem. It will also provide you with a safety net to explore other solutions without breaking the functionality. ### A typical TDD workflow on Exercism: 1. Run the test file and pick one test that's failing. 2. Write some code to fix the test you picked. 3. Re-run the tests to confirm the test is now passing. 4. Repeat from step 1. 5. Submit your solution (`exercism submit /path/to/file`) ## Instructions Submissions are encouraged to be general, within reason. Having said that, it's also important not to over-engineer a solution. It's important to remember that the goal is to make code as expressive and readable as we can. However, solutions to the hello-world exercise will not be reviewed by a person, but by rikki- the robot, who will offer an encouraging word. ## Running tests Execute the tests with: ```bash $ elixir bob_test.exs ``` (Replace `bob_test.exs` with the name of the test file.) ### Pending tests In the test suites, all but the first test have been skipped. Once you get a test passing, you can unskip the next one by commenting out the relevant `@tag :pending` with a `#` symbol. For example: ```elixir # @tag :pending test "shouting" do assert Bob.hey("WATCH OUT!") == "Whoa, chill out!" end ``` Or, you can enable all the tests by commenting out the `ExUnit.configure` line in the test suite. ```elixir # ExUnit.configure exclude: :pending, trace: true ``` For more detailed information about the Elixir track, please see the [help page](http://exercism.io/languages/elixir). ## Source This is an exercise to introduce users to using Exercism [http://en.wikipedia.org/wiki/%22Hello,_world!%22_program](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) ## Submitting Incomplete Problems It's possible to submit an incomplete solution so you can see how others have completed the exercise.