fcheung

event = fn
          {:startElement, _, 'Contents', _, _}, _, state  -> 
            put_in(state[:current], %{})
          {:startElement, _, _name, _, _}, _, state  -> 
            put_in(state[:value], "")

          {:characters, data}, _, state -> 
            update_in(state[:value], &(to_string(data) <> &1))

          {:endElement, _, 'Contents', _}, _, state ->  

fcheung

if Rails::VERSION::MAJOR > 4
  raise "This patch is obsolete and should be removed"
end

class Time
  def compare_with_coercion(other)
  # we're avoiding Time#to_datetime and Time#to_time because they're expensive
    if other.class == Time
      compare_without_coercion(other)
    elsif other.is_a?(Time)

fcheung

require 'benchmark/ips'
require 'set'


set = Set[:$or, :$and, :$nor]
array = %i($or $and $nor)

Benchmark.ips do |x|
x.config(:time => 10, :warmup => 2)

fcheung

gem 'RubyInline'
require 'inline'

class Test
  inline do |builder|
    builder.include "<time.h>"
    builder.c_raw <<-SRC, :arity => 1
      VALUE dummy(VALUE self, VALUE arg){
        VALUE ret = rb_funcall(self, rb_intern("binding"), 0);
        return ret;

fcheung

diff --git a/activerecord/lib/active_record/named_scope.rb b/activerecord/lib/active_record/named_scope.rb
index 83043c2..8c2507e 100644
--- a/activerecord/lib/active_record/named_scope.rb
+++ b/activerecord/lib/active_record/named_scope.rb
@@ -93,7 +93,11 @@ module ActiveRecord
         end
         (class << self; self end).instance_eval do
           define_method name do |*args|
-            scopes[name].call(self, *args)
+            if scoped? :find

fcheung

class Image
	attr_accessor :data
   	def initialize (data)
     	@data = data  
   	end

    def output
      @data.each do |sub|
        sub.each do |cell|
          print cell

fcheung

class Image
  attr_accessor :data
  def initialize (data)
     @data = data  
  end

  def image_blur
    changes = []

    @data.each_with_index do |row, row_index|

fcheung

Going Native

We all love ruby, but sometimes ruby is not enough. Whether it be a performance bottleneck, a killer library written in C or some platform specific functionality you just have to have, sometimes you need to drop down a level.

There have been many talks that show how to take the first steps in writing a ruby C extension. This isn't one of them. I propose instead to give an overview of different ways of extending ruby and show what each approach brings to the table. I intend to cover 'classic' C extensions, RubyInline and FFI across a range of ruby implementations.

About me

fcheung

class Tree
    attr_accessor :payload, :children
    def initialize(payload, children = [])
        @payload = payload
        @children = children
    end 

    def traverse(&block)
      yield self
      @children.each {|child| child.traverse(&block)}

fcheung

Keybase proof

I hereby claim:

• I am fcheung on github.
• I am frederickcheung (https://keybase.io/frederickcheung) on keybase.
• I have a public key whose fingerprint is 9A1B 5755 1E45 1BAE 41D4 8905 C4CD 3D1E B871 B631

To claim this, I am signing this object: