kachayev

(ns kleene)

;;
;; Inspired by "Regexes, Kleene Algebras and Real Ultimate Power"
;; http://plastic-idolatry.com/erik/oslo2014.pdf
;;
;; What do we want to do?...
;;
;; (def p1 (times (Var. "w") (Var. "o") (Var. "w"))
;; (matches? p1 "wow") ;; true

kachayev

sudo bash

cd /usr/local/lib
wget http://launchpad.net/gearmand/trunk/0.18/+download/gearmand-0.18.tar.gz
tar -xvzf gearmand-0.18.tar.gz
cd gearmand-0.18/
apt-get install libboost-program-options-dev uuid-dev libevent-dev build-essential g++
./configure && sudo make && sudo make install
ldconfig

kachayev

;; Channels-driven concurrency with Clojure
;; Clojure variant for code examples from this gist:
;; https://gist.github.com/3124594
;; Primarily taken from Rob Pike's talk on Google I/O 2012:
;; http://www.youtube.com/watch?v=f6kdp27TYZs&feature=youtu.be
;;
;; Concurrency is the key to designing high performance network services. 
;; Clojure provides several concurrency primitives, like futures/promises, atom, agent etc.
;; There is no implementation for "Go channels" in core, but we can use
;; 3rd-party library Lamina to do the same things.

kachayev

## Author: Alexey Kachayev
## Email: kachayev@gmail.com
## Talk: "Functional programming with Python", UA PyCon 2012
## URL: http://ua.pycon.org/static/talks/kachayev/index.html#/

###############################################
## Imitate dictionary functionality
###############################################

def dict_pair((key, value)):

kachayev

package main

import (
    "fmt"
    "time"
    "math/rand"
)

const (
    CUTTING_TIME = 20

kachayev

import scala.actors.Actor
import scala.actors.Actor._

case object Ping
case object Pong
case object Stop

class Ping(count: Int, pong: Actor) extends Actor {
  def act() {
    var pingsLeft = count - 1

kachayev

%% 
%% Solve sleeping barber problem in most general case
%% Task description on Wikipedia:
%% http://en.wikipedia.org/wiki/Sleeping_barber_problem 
%%
%% Additions to classic variant:
%% * many barbers
%% * many clients generators with random timeouts between clients
%% * calculation for total served clients
%% * random time for each client to make barber's job

kachayev

%% 
%% Solve sleeping barber problem in most general case
%% Task description on Wikipedia:
%% http://en.wikipedia.org/wiki/Sleeping_barber_problem 
%%
%% Additions to classic variant:
%% * many barbers
%% * many clients generators with random timeouts between clients
%% * calculation for total served clients
%% * random time for each client to make barber's job

kachayev

%% 
%% Solve sleeping barber problem in most general case
%% Task description on Wikipedia:
%% http://en.wikipedia.org/wiki/Sleeping_barber_problem 
%%
%% Additions to classic variant:
%% * many barbers
%% * many clients generators with random timeouts between clients
%% * calculation for total served clients
%% * random time for each client to make barber's job

kachayev

import Data.List

uniqSubstr :: String -> Int
uniqSubstr = sum . (map pair) . pairwise . sort . tails
    where 
  	pairwise l@(_:ht) = zip l ht
	prefix pre post = length $ takeWhile (uncurry (==)) $ zip pre post 
	pair (pre, post) = length $ drop (prefix pre post) post