F# 用扑克牌创造一只手

Question

I have this code that generates a deck of cards and a function that can randomly choose one of the 52 cards, however. I now need a way to give a play five unique cards that are from the deck and I am not sure how to do that.

Answer 1

As I pointed out in the comments, one way to create this hand is to shuffle a deck then take 5 cards from the top.

type Suit = Diamonds | Hearts | Clubs | Spades
 
type Face =
    | Two | Three | Four | Five | Six | Seven | Eight | Nine | Ten
    | Jack | Queen | King | Ace
 
type Card = { Face: Face; Suit : Suit }

let allFaces = [
   Two; Three; Four; Five; Six; Seven; Eight; Nine; Ten;
   Jack; Queen; King; Ace
]

let allSuits = [ Diamonds; Hearts; Clubs; Spades ]

let fullDeck = [
    for suit in allSuits do
        for face in allFaces do
             yield { Face = face; Suit = suit } 
]

// returns a random card and the remaining deck
let GetCard (deck: Card list) =
    let rand = new System.Random()
    let idx = rand.Next(deck.Length)
    let card = deck.[idx]
    (card, List.except [card] deck)

// shuffle a deck
let rec shuffle = function
    | card :: [] -> [card]
    | deck -> let (card, rest) = GetCard deck
              card :: shuffle rest

let hand deck = deck |> shuffle |> List.take 5

fullDeck |> hand |> printfn "%A"