F# 備忘録

HttpRequest.fs

open FSharp.Data

[<EntryPoint>]
let main argv =
    let req =
        Http.AsyncRequest(
            "http://url/",
            httpMethod = "POST",
            headers = [ "Key", "Value"; ],
            body = FormValues [ "Key", "Value"; ],
            cookies = [ "Key", "Value" ],
            timeout = 5000) |> Async.RunSynchronously

    match req.Body with
    | Binary x -> printfn "response is binary. on size of %d bytes." x.Length
    | Text x -> printfn "response is text. on length of %d." x.Length
    0

MailboxProcessor.fs

type FizzBuzzMessage = int * AsyncReplyChannel<int * string>
let fizzbuzzActor = new MailboxProcessor<FizzBuzzMessage>(fun inbox -> 
    let fizzbuzz = function
        | x when x % 15 = 0 -> "FizzBuzz"
        | x when x % 3 = 0  -> "Fizz"
        | x when x % 5 = 0  -> "Buzz"
        | x                 -> x.ToString()
    async {
        while true do
            let! x, replyChannel = inbox.Receive()
            let converted = x |> fizzbuzz
            replyChannel.Reply (x, converted)
    })

fizzbuzzActor.Start()

[<EntryPoint>]
let main argv =
    let result = fizzbuzzActor.PostAndAsyncReply(fun replyChannel -> 3, replyChannel) |> Async.RunSynchronously
    0

インターフェース.fs

type IPerson =
    abstract Name: string with get, set
    abstract Age: int with get, set
and Person(name, age) =
    let mutable _name = ""
    let mutable _age = 20
    do
        _name <- name
        _age <- age
    interface IPerson with
        member __.Name with get() = _name and set v = _name <- v
        member __.Age with get() = _age and set v = _age <- v
        
[<EntryPoint>]
let main argv =
    let person1: IPerson = Person("タカシ", 20) :> IPerson
    let person2: IPerson = Person("タナカ", 23) :> IPerson
    person1.Greet()
    person2.Greet()
    0

レコード.fs

type PersonInfo = {
    mutable Name: string; (* 可変 *)
    Age: int; (* 固定 *)
}

[<EntryPoint>]
let main argv =
    let info = { Name = "Takashi"; Age = 20 }
    info.Name <- "Takahashi"

    let info2 = { info with Age = 22 } (* Ageを22で追加定義 *)

    0

判別共用体.fs

type OddOrEven =
    | Odd of int
    | Even of int

let test x = if x % 2 = 0 then Even x else Odd x

[<EntryPoint>]
let main argv =
    match test(3) with
    | Odd x -> printfn "number %d is odd." x
    | Even x -> printfn "number %d is even." x
    0

抽象クラス.fs

[<AbstractClass>]
type AbstractPerson() =
    abstract Name: string with get
    abstract Age: int with get
    member this.Greet() =
        printfn "Hello, %s" this.Name

type AbstractPersonImplement(name, age) =
    inherit AbstractPerson()
    override this.Name with get() = name
    override this.Age with get() = age

[<EntryPoint>]
let main argv =
    let person: AbstractPerson = AbstractPersonImplement("Takashi", 20) :> AbstractPerson
    person.Greet()
    0

拡張メソッド.fs

type String with
    member this.ToNumber() = int(this)

[<EntryPoint>]
let main argv =
    let num = "30".ToNumber()
    0

文章で命名.fsx

let ``Hello, world Function!``() = 
    printfn "Hello, World!"

[<EntryPoint>]
let main argv =
    ``Hello, world Function!``()
    0