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nihilismus's solution

to Hello World in the PureScript Track

Published at Sep 10 2020 · 0 comments
Test suite

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.


Purescript setup: npm install -g purescript pulp bower

Install project dependencies: bower install (inside the "hello-world" directory)

Building: pulp build (gotta do this once before the PureScript editor plugins will work)

Running the test: pulp test

Submitting: exercism submit src/HelloWorld.purs


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.


module Test.Main where

import Prelude

import Effect (Effect)
import Test.Unit (TestSuite, suite, test)
import Test.Unit.Main (runTest)
import Test.Unit.Assert as Assert
import Data.Maybe (Maybe(Just, Nothing))
import HelloWorld (helloWorld)

main :: Effect Unit
main = runTest suites

suites :: TestSuite
suites = do
  suite "HelloWorld.helloWorld" do
    test "Hello with no name" do
      Assert.equal "Hello, World!" (helloWorld Nothing)
    test "Hello to a sample name" do
      Assert.equal "Hello, Alice!" (helloWorld (Just "Alice"))
    test "Hello to another sample name" do
      Assert.equal "Hello, Bob!" (helloWorld (Just "Bob"))
module HelloWorld where

import Prelude
import Data.Maybe (Maybe(Just, Nothing))

helloWorld :: Maybe String -> String
helloWorld Nothing = "Hello, World!"
helloWorld (Just name)= "Hello, " <> name <> "!"

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