83 lines
3.0 KiB
Markdown
83 lines
3.0 KiB
Markdown
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# Hello World
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Write a program that greets the user by name, or by saying "Hello, World!" if no name is given.
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["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is the traditional first program for beginning programming in a new language.
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**Note:** You can skip this exercise by running:
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exercism skip $LANGUAGE hello-world
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## Specification
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The `Hello World!` program will greet me, the caller.
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If I tell the program my name is Alice, it will greet me by saying "Hello, Alice!".
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If I neglect to give it my name, it will greet me by saying "Hello, World!"
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## Test-Driven Development
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As programmers mature, they eventually want to test their code.
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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.
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It will also provide you with a safety net to explore other solutions without breaking the functionality.
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### A typical TDD workflow on Exercism:
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1. Run the test file and pick one test that's failing.
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2. Write some code to fix the test you picked.
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3. Re-run the tests to confirm the test is now passing.
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4. Repeat from step 1.
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5. [Submit your solution](http://help.exercism.io/submitting-exercises.html).
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## Instructions
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Submissions are encouraged to be general, within reason. Having said that, it's also important not to over-engineer a solution.
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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.
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* * * *
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For learning resources and help with installation, refer to the
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[Exercism help page][].
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To run the tests provided, you will need to install [Leiningen][].
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To install Leiningen on Mac OS X using [Homebrew][], run the following command:
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brew install leiningen
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For help installing on Linux, Windows or without Homebrew see:
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[Leiningen installation][].
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[Exercism help page]: http://exercism.io/languages/clojure
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[Leiningen]: http://leiningen.org
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[Homebrew]: http://brew.sh
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[Leiningen installation]: https://github.com/technomancy/leiningen#installation
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In an exercise directory, create a `src` directory and a file therein to hold
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your solution. The name of the file should be the exercise name with dashes `-`
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replaced by underscores `_`. For example, if the exercise is called
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`hello-world`, name the solution file `hello_world.clj`.
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Your resulting file tree should look something like this:
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/path/to/hello-world
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├── project.clj
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├── src
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│ └── hello_world.clj
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└── test
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└── hello_world_test.clj
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To run the tests, navigate to the exercise directory and run the following
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command:
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lein test
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## Source
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This is a program to introduce users to using Exercism [view source](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program)
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