69 lines
2.7 KiB
Markdown
69 lines
2.7 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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## Rust Installation
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Refer to the [exercism help page][help-page] for Rust installation and learning
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resources.
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## Writing the Code
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Execute the tests with:
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```bash
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$ cargo test
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```
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All but the first test have been ignored. After you get the first test to
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pass, remove the ignore flag (`#[ignore]`) from the next test and get the tests
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to pass again. The test file is located in the `tests` directory. You can
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also remove the ignore flag from all the tests to get them to run all at once
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if you wish.
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Make sure to read the [Crates and Modules](crates-and-modules) chapter if you
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haven't already, it will help you with organizing your files.
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[help-page]: http://help.exercism.io/getting-started-with-rust.html
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[crates-and-modules]: http://doc.rust-lang.org/stable/book/crates-and-modules.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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