chriseidhof

In this gist we will first show that we can beat the arc challenge
(http://www.paulgraham.com/arcchallenge.html), and then build the library that
shows how we did it. This gist is Literate Haskell and is of course executable. The packages needed are happstack-server and applicative-extras, installable using cabal.

Let's start with some imports (for now, you can ignore these)

> {-# LANGUAGE GADTs, TypeSynonymInstances #-}
> module ArcChallenge where
>
> import Control.Applicative

ademar

// Learn more about F# at http://fsharp.net
open Microsoft.FSharp.Control
open System.Collections.Generic
open System.Threading
open System.IO

type RequestGate(n:int) = 
    let semaphore = new Semaphore(initialCount=n,maximumCount=n);
    member x.AcquireAsync(?timeout) = 
        async {

ademar

// Based on the article 'Combinators for logic programming' by Michael Spivey and Silvija Seres.

let rec inf_seq n =  seq { yield n; yield! inf_seq (n+1) }

let rec lzw f l1 l2 =
    LazyList.delayed ( fun () -> 
    match l1,l2 with
    |LazyList.Nil, _ -> l2
    |_, LazyList.Nil -> l1
    |LazyList.Cons(p1,tail1),LazyList.Cons(p2,tail2)

ry

var http = require('http')
var fork = require('child_process').fork;

function fib(n) {
  if (n < 2) {
    return 1;
  } else {
    return fib(n - 2) + fib(n - 1);
  }
}

sebfisch

Delimited Continuations

Delimited continuations manipulate the control flow of programs. Similar to control structures like conditionals or loops they allow to deviate from a sequential flow of control.

We use exception handling as another example for control flow manipulation and later show how to implement it using delimited continuations. Finally, we show that nondeterminism can also be expressed using delimited continuations.

Exception Handling

tonymorris

class Functor f => Extend f where
  -- CoSelectMany
  extend ::
    (f a -> b)
    -> f a
    -> f b

  -- CoFlatten?
  duplicate ::
    f a

jcdickinson

class IAmDisposable : IDisposable
{
    private int _isDisposed;
    private SomeDisposableThing _disposable1;
    private SomeDisposableBar _disposable2;
    private SomeDisposableBaz _disposable3;

    // Only if you **need** it. You don't though, use SafeHandle.
    //~IAmDisposable()
    //{

dergachev

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

dooglus

// g++ UniversalTimer.o BinaryData.o FileDataPtr.o BtcUtils.o BlockObj.o BlockUtils.o libcryptopp.a -o bootstrap.out -Icryptopp -DUSE_CRYPTOPP -D__STDC_LIMIT_MACROS -lpthread bootstrap.cpp

#include "BlockUtils.h"

int main(void)
{
	string btcdir("/home/chris/.bitcoin");
	string bootstrap(btcdir + "/" + "bootstrap.dat");
	BlockDataManager_FileRefs::GetInstance().SelectNetwork("Main");
	BlockDataManager_FileRefs & bdm = BlockDataManager_FileRefs::GetInstance(); 

migueldeicaza

These instructions will get you Mono compiled from source.

Requirements:
Xcode installed
Command Line Tools installed (part of Xcode)

Then, create a text file with the contents of everything after "=====", save it as "build.sh" in your home directory

Open a terminal window, and type this in your shell: