68 lines
2.6 KiB
Markdown
68 lines
2.6 KiB
Markdown
# 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 installation and learning resources, refer to the
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[exercism help page](http://help.exercism.io/getting-started-with-racket.html).
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You can run the provided tests through DrRacket, or via the command line.
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To run the test through DrRacket, simply open the test file and click the 'Run' button in the upper right.
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To run the test from the command line, simply run the test from the exercise directory. For example, if the test suite is called `hello-world-test.rkt`, you can run the following command:
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```
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raco test hello-world-test.rkt
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```
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which will display the following:
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```
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raco test: (submod "hello-world-test.rkt" test)
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2 success(es) 0 failure(s) 0 error(s) 2 test(s) run
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0
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2 tests passed
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```
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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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