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jaeyson's solution

to Two Fer in the Elm Track

Published at Apr 18 2019 · 0 comments
Test suite

Two-fer or 2-fer is short for two for one. One for you and one for me.

Given a name, return a string with the message:

One for X, one for me.

Where X is the given name.

However, if the name is missing, return the string:

One for you, one for me.

Here are some examples:

Name String to return
Alice One for Alice, one for me.
Bob One for Bob, one for me.
One for you, one for me.
Zaphod One for Zaphod, one for me.

Elm Installation

Refer to the Installing Elm page for information about installing elm.

Writing the Code

The first time you start an exercise, you'll need to ensure you have the appropriate dependencies installed. Thankfully, Elm makes that easy for you and will install dependencies when you try to run tests or build the code.

Execute the tests with:

$ elm-test

Automatically run tests again when you save changes:

$ elm-test --watch

As you work your way through the test suite, be sure to remove the skip <| calls from each test until you get them all passing!



Submitting Incomplete Solutions

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


module Tests exposing (tests)

import Expect
import String
import Test exposing (..)
import TwoFer exposing (twoFer)

tests : Test
tests =
    describe "Two-fer"
        [ test "No name given" <|
            \() ->
                Expect.equal "One for you, one for me." (twoFer Nothing)
        , skip <|
            test "A name given" <|
                \() ->
                    Expect.equal "One for Alice, one for me." (twoFer (Just "Alice"))
        , skip <|
            test "Another name given" <|
                \() ->
                    Expect.equal "One for Bob, one for me." (twoFer (Just "Bob"))
module TwoFer exposing (twoFer)

twoFer : Maybe String -> String
twoFer name =
  case name of
    Just str ->
      "One for " ++ str ++ ", one for me."
    Nothing ->
      "One for you, one for me."

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