54 lines
2.3 KiB
Markdown
54 lines
2.3 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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The Scala exercises assume an SBT project scheme. The exercise solution source
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should be placed within the exercise directory/src/main/scala. The exercise
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unit tests can be found within the exercise directory/src/test/scala.
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To run the tests simply run the command `sbt test` in the exercise directory.
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For more detailed info about the Scala track see the [help
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page](http://help.exercism.io/getting-started-with-scala.html).
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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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