Gab-km

type Message = string * AsyncReplyChannel<string>

let agent = new MailboxProcessor<Message>(fun inbox ->
    let rec loop count =
        async {
            System.Threading.Thread.Sleep(1000) // something busy
            let! msg, replyChannel = inbox.Receive()
            printfn "%s" msg
            replyChannel.Reply(msg + msg)
            return! loop (count + 1)

Gab-km

namespace FSharp.Monad

type CoYoneda<'U> =
  abstract Run: obj -> 'U

type CoYoneda<'F, 'A>(fi: 'F, k: CoYoneda<'A>) = class end

module CoYoneda =
  
  let apply fa k =

Gab-km

[System.Reflection.Assembly]::LoadFile('/path/to/MongoDB.Driver.dll')
[System.Reflection.Assembly]::LoadFile('/path/to/MongoDB.Bson.dll')

$client = New-Object MongoDB.Driver.MongoClient("mongodb://hostname")
$server = $client.GetServer()
$db = $server.GetDatabase("test")
$user = $db.GetCollection("User")

foreach($doc in $user.FindAll() {
  [System.Console]::WriteLine($doc)

Gab-km

// Interface
type ICallable<'a, 'b> =
    abstract member callback: 'a -> 'b

// concrete class
type Callable<'a, 'b>(f: 'a -> 'b) =
    interface ICallable<'a, 'b> with
        member self.callback x = f x

// computation builder

Gab-km

これは、 @kmizu さんの「初学者向けの Scala Tips」を勝手に F# にポートした記事です。

Gab-km

class FizzBuzzExtractor[T](f: T => Boolean){
  def unapply(t: T) = f(t)
}

val FizzBuzz = new FizzBuzzExtractor[Int](_ % 15 == 0)
object Fizz extends FizzBuzzExtractor[Int](_ % 3 == 0)
object Buzz extends FizzBuzzExtractor[Int](_ % 5 == 0)

object FizzBuzzRunner {
  def run(num: Int) = num match {

Gab-km

# -*- coding: utf-8 -*-

def class_extender(cls):
  def __init__(self, value):
    self.value = value
  cls.__init__ = __init__
  return cls

@class_extender
class Hoge:

Gab-km

let undefined _ = failwith "undefined"
let hoge (x : string) : int = undefined()

Gab-km

何故私は Heroku から離れたか、および新しい AWS セットアップのメモ

原著者

Adrian Holovaty

原文

Why I left Heroku, and notes on my new AWS setup

金曜日、私は Heroku から Amazon Web Services(AWS) を直接使うように Soundslice を移行しました。私はこの変更ができてとても、そうとても嬉しくて、私がどうやったかということと、もし皆さんが同じような立場だったら何故それを検討すべきかということについて広く伝えたいと思います。

Gab-km

open System

//============================================
// IOモナド
//============================================
module IO =
    type IO<'a> = IO of (unit -> 'a)

    type IOBuilder() =
        member this.Bind (IO x, f) = f (x())