dolzenko

! Swap Alt and Cmd keys.
keycode 37 =    Control_L
keycode 133 =   Alt_L Meta_L
keycode 64 =    Super_L
keycode 108 =   Super_R
keycode 134 =   Alt_L Meta_L
keycode 108 =   Control_R       Multi_key
clear Shift
clear Lock
clear Control

kogakure

# .irbrc
if defined?(Rails) && Rails.production?
  conf = IRB.conf[:PROMPT][IRB.conf[:PROMPT_MODE]]
  red = "\033[0;31m"
  reset = "\033[0m"
  [:PROMPT_S, :PROMPT_C].each do |p|
    conf[p].gsub!(/^(.*)$/, "#{red}\\1#{reset}")
  end
  conf[:PROMPT_I] = "#{red}%N(%m):%03n:%i (PRODUCTION) > #{reset}"
end

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

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

chetan

YARD CHEATSHEET http://yardoc.org

May 2020 - updated fork: https://gist.github.com/phansch/db18a595d2f5f1ef16646af72fe1fb0e

cribbed from http://pastebin.com/xgzeAmBn

Templates to remind you of the options and formatting for the different types of objects you might want to document using YARD.

Modules

marcinbunsch

# Put this file in config/initializers/irb.rb
# Works in Rails 3.0+, should also work in 2.3

# Override the IRB, to provide the Rails environment in the prompt
module IRB

  class << self
    def setup_with_prompt_override(ap_path)
      setup_without_prompt_override(ap_path)
      env = (Rails.env.to_sym == :production ? "\033[00;31mPRODUCTION\033[00m" : Rails.env)

dolzenko

> Rack::Utils::SYMBOL_TO_STATUS_CODE
{
continue:                         100,
switching_protocols:              101,
processing:                       102,
ok:                               200,
created:                          201,
accepted:                         202,
non_authoritative_information:    203,
no_content:                       204,