Bandwagoner

// Define a record
type Address =
    { Street: string
      HouseNumber: int }

// Create a record
let oldAddress: Address =
    { Street = "Main Street"
      HouseNumber = 17 }

// Single-line alternative
type ConciseAddress = { Street: string; HouseNumber: int }
let conciseAddress: ConciseAddress = { Street = "Main Street"; HouseNumber = 17 }

// Copy the old address but change the house number
let newAddress: Address = { oldAddress with HouseNumber = 86 }
newAddress.Street      // => "Main Street"
newAddress.HouseNumber // => 86

let myAddress: Address = { Street = "Broadway"; HouseNumber = 123 }
let { Street = myStreet; HouseNumber = myHouseNumber } = myAddress

match myAddress with
| { HouseNumber = 1 } -> printfn "First house"
| { HouseNumber = houseNumber; Street = street } -> printfn "House number %d on %s" houseNumber street
// => "House number 123 on Broadway

Instructions

In this exercise you're a big sports fan and you've just discovered a passion for NBA basketball. Being new to NBA basketball, you're doing a deep dive into NBA history, keeping track of teams, coaches, their win/loss stats and comparing them against each other.

As you don't yet have a favorite team, you'll also be developing an algorithm to figure out whether to root for a particular team.

You have seven tasks to help you develop your proprietary root-for-a-team algorithm.

1. Define the model

Define the Coach record with the following two fields:

• Name: the coach's name, of type string.
• FormerPlayer: indicates if the coach was a former player, of type bool.

Define the Stats record with the following two fields:

• Wins: the number of wins, of type int.
• Losses: the number of losses, of type int.

Define the Team record with the following three fields:

• Name: the team's name, of type string.
• Coach: the team's coach, of type Coach.
• Stats: the team's stats, of type Stats.

2. Create a team's coach

Implement the createCoach function that takes the coach name and its former player status as parameters, and returns its Coach record:

createCoach "Larry Bird" true
// => { Name = "Larry Bird"; FormerPlayer = true }

3. Create a team's stats

Implement the createStats function that takes the number of wins and the number losses as parameters, and returns its Stats record:

createStats 58 24
// => { Wins = 58; Losses = 24 }

4. Create a team

Implement the createTeam function that takes the team name, coach and record as parameters, and returns its Team record:

let coach = createCoach "Larry Bird" true
let record = createStats 58 24
createTeam "Indiana Pacers" coach record
// => { Name = "Indiana Pacers"
//      Coach = { Name = "Larry Bird"; FormerPlayer = true }
//      Stats = { Wins = 58; Losses = 24 } }

5. Replace the coach

NBA owners being impatient, you found that bad team results would often lead to the coach being replaced. Implement the replaceCoach function that takes the team and its new coach as parameters, and returns the team but with the new coach:

let coach = createCoach "Larry Bird" true
let record = createStats 58 24
let team = createTeam "Indiana Pacers" coach record

let newCoach = createCoach "Isiah Thomas" true
replaceCoach team newCoach
// => { Name = "Indiana Pacers"
//      Coach = { Name = "Isiah Thomas"; FormerPlayer = true }
//      Stats = { Wins = 58; Losses = 24 } }

6. Check for same team

While digging into stats, you're keeping lists of teams and their records. Sometimes, you get things wrong and there are duplicate entries on your list. Implement the isSameTeam function that takes two teams and returns true if they are the same team; otherwise, return false:

let pacersCoach = createCoach "Larry Bird" true
let pacersStats = createStats 58 24
let pacersTeam = createTeam "Indiana Pacers" pacersCoach pacersStats

let lakersCoach = createCoach "Del Harris" false
let lakersStats = createStats 61 21
let lakersTeam = createTeam "LA Lakers" lakersCoach lakersStats

isSameTeam pacersTeam lakersTeam
// => false

7. Check if you should root for a team

Having looked at many teams and matches, you've come up with an algorithm. If one of the following is true, you root for that team:

• The coach's name is "Gregg Popovich"
• The coach is a former player
• The team's name is the "Chicago Bulls"
• The team has won 60 or more games
• The team has more losses than wins

Implement the rootForTeam function that takes a team and returns true if you should root for that team; otherwise, return false:

let spursCoach = createCoach "Gregg Popovich" false
let spursStats = createStats 56 26
let spursTeam = createTeam "San Antonio Spurs" spursCoach spursStats
rootForTeam spursTeam
// => true