nicolemon's solution to Hello World on the Haskell track

Instructions

Test suite

Solution

The classical introductory exercise. Just say "Hello, World!".

"Hello, World!" is the traditional first program for beginning programming in a new language or environment.

The objectives are simple:

Write a function that returns the string "Hello, World!".
Run the test suite and make sure that it succeeds.
Submit your solution and check it at the website.

If everything goes well, you will be ready to fetch your first real exercise.

Hints

To complete this exercise, you need to implement the hello function.

You will find the type signature for hello already in place, but it is up to you to define the function.

Getting Started

Please refer to the installation and learning help pages.

Running the tests

To run the test suite, execute the following command:

stack test

If you get an error message like this...

No .cabal file found in directory

You are probably running an old stack version and need to upgrade it.

Otherwise, if you get an error message like this...

No compiler found, expected minor version match with...
Try running "stack setup" to install the correct GHC...

Just do as it says and it will download and install the correct compiler version:

stack setup

Running GHCi

If you want to play with your solution in GHCi, just run the command:

stack ghci

Feedback, Issues, Pull Requests

The exercism/haskell repository on GitHub is the home for all of the Haskell exercises.

If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue. We'll do our best to help you!

Source

This is an exercise to introduce users to using Exercism http://en.wikipedia.org/wiki/%22Hello,_world!%22_program

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Tests.hs

import Test.Hspec        (Spec, it, shouldBe)
import Test.Hspec.Runner (configFastFail, defaultConfig, hspecWith)

import HelloWorld (hello)

main :: IO ()
main = hspecWith defaultConfig {configFastFail = True} specs

specs :: Spec
specs = it "hello" $
          hello `shouldBe` "Hello, World!"

-- 5c542864b011fb742aa95ca950d3473ce168ec8c

module HelloWorld (hello) where

hello :: String
hello = "Hello, World!"

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nicolemon's solution

to Hello World in the Haskell Track