# Hello World

Write a program that greets 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 $LANGUAGE hello-world

## Specification

The `Hello World!` program will greet me, the caller.

If I tell the program my name is Alice, it will greet me by saying "Hello, Alice!".

If I neglect to give it my name, it will greet me by saying "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](http://help.exercism.io/submitting-exercises.html).

## 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 be not be reviewed by a person, but by rikki- the robot, who will offer an encouraging word.

* * * *

For learning resources and help with installation, refer to the
[Exercism help page][].

To run the tests provided, you will need to install [Leiningen][].

To install Leiningen on Mac OS X using [Homebrew][], run the following command:

    brew install leiningen

For help installing on Linux, Windows or without Homebrew see:
[Leiningen installation][].

[Exercism help page]: http://exercism.io/languages/clojure
[Leiningen]: http://leiningen.org
[Homebrew]: http://brew.sh
[Leiningen installation]: https://github.com/technomancy/leiningen#installation

In an exercise directory, create a `src` directory and a file therein to hold
your solution. The name of the file should be the exercise name with dashes `-`
replaced by underscores `_`.  For example, if the exercise is called
`hello-world`, name the solution file `hello_world.clj`.

Your resulting file tree should look something like this:

    /path/to/hello-world
    ├── project.clj
    ├── src
    │   └── hello_world.clj
    └── test
        └── hello_world_test.clj


To run the tests, navigate to the exercise directory and run the following
command:

    lein test

## Source

This is a program to introduce users to using Exercism [view source](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program)