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spahrson's solution

to Bob in the Elm Track

Published at May 27 2019 · 0 comments
Instructions
Test suite
Solution

Bob is a lackadaisical teenager. In conversation, his responses are very limited.

Bob answers 'Sure.' if you ask him a question.

He answers 'Whoa, chill out!' if you yell at him.

He answers 'Calm down, I know what I'm doing!' if you yell a question at him.

He says 'Fine. Be that way!' if you address him without actually saying anything.

He answers 'Whatever.' to anything else.

Bob's conversational partner is a purist when it comes to written communication and always follows normal rules regarding sentence punctuation in English.

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!

Source

Inspired by the 'Deaf Grandma' exercise in Chris Pine's Learn to Program tutorial. http://pine.fm/LearnToProgram/?Chapter=06

Submitting Incomplete Solutions

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

Tests.elm

module Tests exposing (anyCharacter, character, gibberish, gibberishQuestion, listOfCharacters, tests, uppercaseCharacter, uppercaseGibberish)

import Bob
import Char
import Expect
import Random
import String
import Test exposing (..)


tests : Test
tests =
    describe "Bob"
        [ test "stating something" <|
            \() ->
                Expect.equal "Whatever."
                    (Bob.hey "Tom-ay-to, tom-aaaah-to.")
        , skip <|
            test "shouting" <|
                \() ->
                    Expect.equal
                        "Whoa, chill out!"
                        (Bob.hey "WATCH OUT!")
        , skip <|
            test "shouting gibberish" <|
                \() ->
                    Expect.equal
                        "Whoa, chill out!"
                        (Bob.hey (uppercaseGibberish 10))
        , skip <|
            test "asking a question" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "Does this cryogenic chamber make me look fat?")
        , skip <|
            test "asking a numeric question" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "You are, what, like 15?")
        , skip <|
            test "asking gibberish" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey (gibberishQuestion 20))
        , skip <|
            test "talking forcefully" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "Let's go make out behind the gym!")
        , skip <|
            test "using acronyms in regular speech" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "It's OK if you don't want to go to the DMV.")
        , skip <|
            test "forceful questions" <|
                \() ->
                    Expect.equal
                        "Calm down, I know what I'm doing!"
                        (Bob.hey "WHAT THE HELL WERE YOU THINKING?")
        , skip <|
            test "shouting numbers" <|
                \() ->
                    Expect.equal
                        "Whoa, chill out!"
                        (Bob.hey "1, 2, 3 GO!")
        , skip <|
            test "only numbers" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "1, 2, 3")
        , skip <|
            test "question with only numbers" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "4?")
        , skip <|
            test "shouting with special characters" <|
                \() ->
                    Expect.equal
                        "Whoa, chill out!"
                        (Bob.hey "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!")
        , skip <|
            test "shouting with no exclamation mark" <|
                \() ->
                    Expect.equal
                        "Whoa, chill out!"
                        (Bob.hey "I HATE YOU")
        , skip <|
            test "statement containing a question mark" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "Ending with ? means a question.")
        , skip <|
            test "prattling on" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "Wait! Hang on. Are you going to be OK?")
        , skip <|
            test "silence" <|
                \() ->
                    Expect.equal
                        "Fine. Be that way!"
                        (Bob.hey "")
        , skip <|
            test "prolonged silence" <|
                \() ->
                    Expect.equal
                        "Fine. Be that way!"
                        (Bob.hey "       ")
        , skip <|
            test "alternate silences" <|
                \() ->
                    Expect.equal
                        "Fine. Be that way!"
                        (Bob.hey "\t  \n  \t   ")
        , skip <|
            test "on multiple line questions" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "\nDoes this cryogenic chamber make me look fat?\nno")
        , skip <|
            test "ending with whitespace" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "Okay if like my  spacebar  quite a bit?   ")
        , skip <|
            test "no letters" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "1, 2, 3")
        , skip <|
            test "question with no letters" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey "4?")
        , skip <|
            test "statement containing question mark" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "Ending with ? means a question.")
        , skip <|
            test "non-letters with question" <|
                \() ->
                    Expect.equal
                        "Sure."
                        (Bob.hey ":) ?")
        , skip <|
            test "starting with whitespace" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "         hmmmmmmm...")
        , skip <|
            test "other whitespace" <|
                \() ->
                    Expect.equal
                        "Fine. Be that way!"
                        (Bob.hey "\n\u{000D} \t")
        , skip <|
            test "non-question ending with whitespace" <|
                \() ->
                    Expect.equal
                        "Whatever."
                        (Bob.hey "This is a statement ending with whitespace      ")
        ]


character : Int -> Int -> Random.Generator Char
character start end =
    Random.map Char.fromCode (Random.int start end)


anyCharacter : Random.Generator Char
anyCharacter =
    character 32 126


uppercaseCharacter : Random.Generator Char
uppercaseCharacter =
    character 65 90


listOfCharacters : Int -> Random.Generator Char -> Random.Generator (List Char)
listOfCharacters length characterList =
    Random.list length characterList


gibberish : Int -> Random.Generator Char -> String
gibberish length characterList =
    Tuple.first (Random.step (Random.map String.fromList (listOfCharacters length characterList)) (Random.initialSeed 424242))


uppercaseGibberish : Int -> String
uppercaseGibberish length =
    gibberish length uppercaseCharacter


gibberishQuestion : Int -> String
gibberishQuestion length =
    gibberish length anyCharacter ++ "?"
module Bob exposing (hey)


hey : String -> String
hey remark =
    let
        text =
            String.trim remark
    in
    if String.isEmpty text then
        "Fine. Be that way!"

    else
        case ( isYell text, isQuestion text ) of
            ( True, True ) ->
                "Calm down, I know what I'm doing!"

            ( False, True ) ->
                "Sure."

            ( True, False ) ->
                "Whoa, chill out!"

            ( False, False ) ->
                "Whatever."


isYell : String -> Bool
isYell text =
    let
        striped =
            String.filter Char.isAlpha text
    in
    not (String.isEmpty striped) && String.all Char.isUpper striped


isQuestion : String -> Bool
isQuestion text =
    String.endsWith "?" text

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