brajeshwar

Sublime Text 2 – Useful Shortcuts (Mac OS X)

General

⌘T	go to file
⌘⌃P	go to project
⌘R	go to methods
⌃G	go to line
⌘KB	toggle side bar
⌘⇧P	command prompt

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

sferik

#!/usr/bin/env sh

brew update
brew install rbenv
brew install ruby-build
brew install openssl
CONFIGURE_OPTS=--with-openssl-dir=`brew --prefix openssl` rbenv install 2.0.0-preview1

mrichie

# First, make sure that you have the most recent rvm. Several bugs with 2.0.0-preview1
# have recently been fixed.
#
# Second, the openssl that comes with MacOS is too old for Ruby 2.0. You need to install
# a newer one with homebrew or the rvm pkg command.

# Option 1, with homebrew openssl:

brew update
brew install openssl

loicdescotte

Scala for comprehension translation helper

"For comprehension" is a another syntaxe to use map, flatMap and withFilter (or filter) methods.

yield keyword is used to aggregate values in the resulting structure.

This composition can be used on any type implementing this methods, like List, Option, Future...

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

davidallsopp

/**
 * Examples of writing mixed unit/property-based (ScalaCheck) tests.
 *
 * Includes tables and generators as well as 'traditional' tests.
 *
 * @see http://www.scalatest.org/user_guide/selecting_a_style
 * @see http://www.scalatest.org/user_guide/property_based_testing
 */

import org.scalatest._

patriciogonzalezvivo

Install Homebrew

ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go)"

Add PATH to ~/.bash_profile and ~/.zshrc

export PATH=/usr/local/bin:$PATH

pathikrit

val n = 9
val s = Math.sqrt(n).toInt
type Board = IndexedSeq[IndexedSeq[Int]]
 
def solve(board: Board, cell: Int = 0): Option[Board] = (cell%n, cell/n) match {
  case (r, `n`) => Some(board)
  case (r, c) if board(r)(c) > 0 => solve(board, cell + 1)
  case (r, c) =>
    def guess(x: Int) = solve(board.updated(r, board(r).updated(c, x)), cell + 1)  
    val used = board.indices.flatMap(i => Seq(board(r)(i), board(i)(c), board(s*(r/s) + i/s)(s*(c/s) + i%s)))

odersky

/** This is in reference to @tploecat's blog http://tpolecat.github.io/2015/04/29/f-bounds.html
 *  where he compares F-bounded polymorphism and type classes for implementing "MyType".
 * 
 *  Curiously, the in my mind obvious solution is missing: Use abstract types.
 * 
 *  A lot of this material, including an argument against F-bounded for the use-case
 *  is discussed in:
 * 
 *  Kim B. Bruce, Martin Odersky, Philip Wadler:
 *  A Statically Safe Alternative to Virtual Types. ECOOP 1998: 523-549