zenkay

Ruby, RVM and Mountain Lion

Key problems

Mountain Lion (10.8) has three main difference compared to Lion (10.7):

• XCode 4.4 does not install Command Line Tools by default
• X11 isn't available anymore
• The installed version of OpenSSL has some bugs

How to work around

practicingruby

require 'socket'

module EventEmitter
  def _callbacks
    @_callbacks ||= Hash.new { |h, k| h[k] = [] }
  end

  def on(type, &blk)
    _callbacks[type] << blk
    self

bravoecho

require 'pry'

data = {
  a: {
    alfa: "alfa",
    beta: "beta"
  },
  b: 2,
  c: {
    alfa: {

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:

jpignata

require "raindrops"

class UnicornConnectionMonitor
  def initialize(app, options = {})
    @app = app
    @statsd = options.fetch(:statsd)
  end

  def call(env)
    if linux? && unicorn?

jstorimer

This is a proof-of-concept of a couple of concurrent data structures written in Ruby.

The implementations are heavily commented for those interested. There are benchmarks (with results) included below. The results are interesting, but, as always, take with a grain of salt.

Data structures

AtomicLinkedQueue is a lock-free queue, built on atomic CAS operations.

rcrowley

package main

import (
	"log"
	"net"
	"os"
	"os/signal"
	"sync"
	"syscall"
	"time"

rick

$("button.mark-all-as-read").parent().prepend('<button class="box-action mute-all-unread css-truncate tooltipped upwards" original-title="mute all unread notifications"> <span class="octicon octicon-mute"></span> </button>');

$('button.mute-all-unread').click(function(event) {
  // mute all unread notifications
  $(this).parent().parent().parent().find('li.unread').find('.js-mute-notification button').click();
  return false;
});

debasishg

General Background and Overview

1. Probabilistic Data Structures for Web Analytics and Data Mining : A great overview of the space of probabilistic data structures and how they are used in approximation algorithm implementation.
2. Models and Issues in Data Stream Systems
3. Philippe Flajolet’s contribution to streaming algorithms : A presentation by Jérémie Lumbroso that visits some of the hostorical perspectives and how it all began with Flajolet
4. Approximate Frequency Counts over Data Streams by Gurmeet Singh Manku & Rajeev Motwani : One of the early papers on the subject.
5. [Methods for Finding Frequent Items in Data Streams](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.187.9800&rep=rep1&t

lelandbatey

Description

This simple script will take a picture of a whiteboard and use parts of the ImageMagick library with sane defaults to clean it up tremendously.

The script is here:

#!/bin/bash
convert "$1" -morphology Convolve DoG:15,100,0 -negate -normalize -blur 0x1 -channel RBG -level 60%,91%,0.1 "$2"

Results