84 lines
2.1 KiB
Markdown
84 lines
2.1 KiB
Markdown
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# Hello World
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The classical introductory exercise. Just say "Hello, World!".
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["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is
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the traditional first program for beginning programming in a new language
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or environment.
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The objectives are simple:
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- Write a function that returns the string "Hello, World!".
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- Run the test suite and make sure that it succeeds.
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- Submit your solution and check it at the website.
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If everything goes well, you will be ready to fetch your first real exercise.
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## Hints
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To complete this exercise, you need to implement the `hello` function.
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You will find the type signature for `hello` already in place,
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but it is up to you to define the function.
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## Getting Started
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For installation and learning resources, refer to the
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[exercism help page](http://exercism.io/languages/haskell).
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## Running the tests
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To run the test suite, execute the following command:
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```bash
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stack test
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```
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#### If you get an error message like this...
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```
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No .cabal file found in directory
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```
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You are probably running an old stack version and need
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to upgrade it.
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#### Otherwise, if you get an error message like this...
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```
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No compiler found, expected minor version match with...
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Try running "stack setup" to install the correct GHC...
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```
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Just do as it says and it will download and install
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the correct compiler version:
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```bash
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stack setup
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```
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## Running *GHCi*
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If you want to play with your solution in GHCi, just run the command:
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```bash
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stack ghci
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```
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## Feedback, Issues, Pull Requests
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The [exercism/haskell](https://github.com/exercism/haskell) repository on
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GitHub is the home for all of the Haskell exercises.
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If you have feedback about an exercise, or want to help implementing a new
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one, head over there and create an issue. We'll do our best to help you!
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## Source
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This is an exercise to introduce users to using Exercism [http://en.wikipedia.org/wiki/%22Hello,_world!%22_program](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program)
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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