virtualsafety

package main
 
import (
  "io/ioutil"
  "log"
  "net"
  "net/http"
  "net/url"
  "strings"
  "time"

virtualsafety

package main

import (
	"bytes"
	"encoding/hex"
	"flag"
	"fmt"
	"io"
	"log"
	"net"

virtualsafety

// Implementation of a UDP proxy

package main

import (
	"flag"
	"fmt"
	"log"
	"net"
	"os"

virtualsafety

Backend Architectures

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• Scaling Twitter
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virtualsafety

import Control.Monad.State
import Control.Monad.Identity
import Data.Char(toUpper)
 

test1 :: State Int (Int,Int)
test1 = do
    a <- get
    modify (+1)
    b <- get

virtualsafety

keliven@keliven:~/haskell_example$ cat fib_3.hs
import System.Environment

fib = 0:1:(zipWith (+) fib (tail fib))
 

main = do
  args <- getArgs
  print $ (fib !!) $ read $ args !! 0

virtualsafety

module Main where

import Text.Parsec
import Text.Parsec.String

input_text :: String
input_text = "foo123:"

main :: IO ()
main = do

virtualsafety

module AVLTree where 
data BT = L | N Int BT BT deriving (Show, Eq)

-- Nice, small and useful functions
empty = L

-- You could say, depth L == Nothing depth (N v L L) == Just 0, but works for
-- me better this way:
depth L = 0
depth (N _ t u) = (max (depth t) (depth u)) + 1

virtualsafety

import Data.Maybe (isJust)

data Tree a = Leaf | Node (Tree a) a (Tree a)

replace :: a -> Tree a -> Tree a
replace a Leaf = Node Leaf a Leaf
replace a (Node l _ r) = Node l a r

rotateR :: Tree a -> Tree a
rotateR (Node (Node x a y) b z) = Node x a (Node y b z)

virtualsafety

{-# LANGUAGE GADTs #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE StandaloneDeriving #-}
module RedBlackTree where

data Zero 
data Succ n
type One = Succ Zero

data Black