Andrew White pixeltrix

Performance Links

RailsConf 2015 Videos

DHH Keynote
[Tenderlove Keynote][2]
[Koichi Sasada - What’s happening in your Rails app?][3]
[Richard Scheeman - Speed Science][4]

When should you use DateTime and when should you use Time?

It's a common misconception that [William Shakespeare][1] and [Miguel de Cervantes][2] died on the same day in history - so much so that UNESCO named April 23 as [World Book Day because of this fact][3]. However because England hadn't yet adopted [Gregorian Calendar Reform][4] (and wouldn't until [1752][5]) their deaths are actually 10 days apart. Since Ruby's Time class implements a [proleptic Gregorian calendar][6] and has no concept of calendar reform then there's no way to express this. This is where DateTime steps in:

>> shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND)
=> Tue, 23 Apr 1616 00:00:00 +0000
>> cervantes = DateTime.iso8601('1616-04-23', Date::ITALY)
=> Sat, 23 Apr 1616 00:00:00 +0000

Keybase proof

I hereby claim:

I am pixeltrix on github.
I am pixeltrix (https://keybase.io/pixeltrix) on keybase.
I have a public key whose fingerprint is 64AC 62AF 61FE B618 2F5B D9AA E2AE 198C 7AE0 543D

To claim this, I am signing this object:

	$ ruby template_engine_shootout.rb
	Fetching gem metadata from https://rubygems.org/....
	Fetching version metadata from https://rubygems.org/..
	Resolving dependencies...
	Using benchmark-ips 2.3.0
	Using erubis 2.7.0
	Using tilt 2.0.1
	Using haml 4.0.7
	Using temple 0.7.6
	Using slim 3.0.6

	<%= f.label :appointment_time %><br>
	<%= f.fields_for :appointment_time, @person.appointment_time do \|t\| %>
	<%= t.text_field :day, size: 2, placeholder: 'DD' %> /
	<%= t.text_field :month, size: 2, placeholder: 'MM' %> /
	<%= t.text_field :year, size: 4, placeholder: 'YYYY' %> -
	<%= t.text_field :hour, size: 2, placeholder: 'HH' %> :
	<%= t.text_field :min, size: 2, placeholder: 'MM' %>
	<% end %>

	class Person < ActiveRecord::Base

	validates :name, presence: true, length: { maximum: 255 }
	validates :date_of_birth_day, presence: true, format: /\A\d{1,2}\z/
	validates :date_of_birth_month, presence: true, format: /\A\d{1,2}\z/
	validates :date_of_birth_year, presence: true, format: /\A\d{4}\z/
	validates :date_of_birth, presence: true

	validate do
	if building_date_of_birth?

	class Product < ActiveRecord::Base
	has_many :category_products, dependent: :delete_all
	has_many :categories, through: :category_products, ->{ order(:name) }
	end

	class CategoryProduct < ActiveRecord::Base
	belongs_to :category
	belongs_to :product
	end

	<!doctype html>
	<html>
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
	<style>
	h1,
	h2,
	h3,
	h4,

	require 'openssl'

	class MessageEncryptor
	class << self
	include OpenSSL

	def delivering_email(message)
	encrypted_message = sign_and_encrypt(message.encoded, message.to)
	overwrite_body(message, encrypted_message)
	overwrite_headers(message, encrypted_message)

	class Kid
	attr_reader :name, :naughty, :nice

	def initialize(name, options = {})
	@name = name
	@naughty = options.fetch(:naughty, false)
	@nice = options.fetch(:nice, false)
	end

	alias_method :naughty?, :naughty