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// 今のJSXだと何書いてるかわからん
var adder1 = function(x: int): function(: int): int {
  return function(y: int): int { return x + y; };
};
// 俺の提案でも->で死ぬるが、
var adder2 = (x: int): (int) -> int -> (y: int): int -> x + y;
// 無理してsimple lambda使わなければ、それなりに読める
var adder3 = (x: int): (int) -> int -> {
  return (y: int): int -> x + y;
};

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let inline speak (a: ^a) = 
    let x = (^a : (member Name: string) (a))
    printfn "I'm %s" x
    let y = (^a : (member talk: unit -> string) (a))
    printfn "I say %s" y

//type Duck = 
//    { Name : string } // Name is not property in F# 2.0
//        
//    member x.talk() = "quackity quack"

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// fsiで

type Hoge() =
  member this.Piyo(i: int) = "piyo1"
  member this.Piyo(s: string) = "piyo2"

let f () =
  <@ (fun (h: Hoge) -> h.Piyo(42)) @>;; // <- ここと、

type Hoge with

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// ローカル変数のletは、C#のvarと同じものと思っておけば(とりあえずは)よい
// var x = 42;

let x = 42

// 関数定義のletは、C#で
// var f = new Func<int, string>(i => i.ToString());
// という書き方で、関数定義もできてしまう、と考える

let f (i: int) = i.ToString()

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public class Hoge
{
    // 処理結果コードを返す
    public string Piyo(...) { ... }

    public readonly int ResultA;
    public readonly string ResultB;
}

var code = h.Piyo(...);

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
 
namespace Proofcafe
{
    public static class TaskMonad

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interface A {
  hoge(str:string): string;
}

interface B {
  hoge(str:string): string;
}

class AImpl implements A {
  hoge(str) {

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public abstract class Base<T>
{
  public abstract T Method();
}

public class Sub1 : Base<int>
{
  public override int Method() { return 0; }
}

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using System;

namespace LangExt.Playground
{
    public sealed class LazyVal<T>
    {
        T value;
        bool hasValue = false;
        readonly Func<T> f;

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using System;
using System.ComponentModel;

namespace LangExt.Playground
{
    public sealed class LazyVal<T>
    {
        readonly Func<T> f;
        bool hasValue = false;
        T value;