Scala vs Ruby
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A comparison between the programming languages Scala and Ruby
Transcript of Scala vs Ruby
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<relationships> <ejb-relation> <ejb-relation-name>a-b</ejb-relation-name> <ejb-relationship-role> <!-- A => B --> <ejb-relationship-role-name>a2b</ejb-relationship-role-name> <multiplicity>One</multiplicity> <relationship-role-source> <ejb-name>A</ejb-name> </relationship-role-source> <cmr-field> <cmr-field-name>b</cmr-field-name> </cmr-field> </ejb-relationship-role> <ejb-relationship-role> <!-- B => A --> <ejb-relationship-role-name>b2a</ejb-relationship-role-name> <multiplicity>One</multiplicity> <relationship-role-source> <ejb-name>B</ejb-name> </relationship-role-source> </ejb-relationship-role> </ejb-relation></relationships>
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Functionalprogramming
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Functionalprogramming
APIs
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Functionalprogramming
APIs
gems
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Functionalprogramming
APIs
gemsEasy to use
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Functionalprogramming ?
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Functionalprogramming ?
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Functionalprogramming ?
APIs ?
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Functionalprogramming ?
APIs ?
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Functionalprogramming ?
APIs ?
gems ?
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Functionalprogramming ?
APIs ?
gems ?
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Functionalprogramming ?
APIs ?
gems ?Easy to use ?
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Functionalprogramming ?
APIs ?
gems ?Easy to use ?
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VS
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VSFIGHT13
VSDRAWSort of ...
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WHY A DRAW ?
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WHY A DRAW ?
let’s talk about languages
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WHY A DRAW ?
let’s talk about languages
let’s frameworkise
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WHY A DRAW ?
let’s talk about languages
let’s frameworkise
let’s deploy
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WHY A DRAW ?
let’s talk about languages
let’s frameworkise
let’s meet people
let’s deploy
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LET’S TALK ABOUT LANGUAGES
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BEST THING ABOUT
THE
SCALA & RUBY16
No
at the end of lines
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No
at the end of lines;
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No
at the end of lines;
Scala1
Ruby1
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λ18
list.filter(_ % 2 == 0)
list.filter { e: Int => (e % 2 == 0))}
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list.filter(_ % 2 == 0)
list.select do |e| e % 2 == 0end
list.filter { e: Int => (e % 2 == 0))}
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list.filter(_ % 2 == 0)
list.select do |e| e % 2 == 0end
list.filter { e: Int => (e % 2 == 0))}
Scala2
Ruby2
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TYPES !
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STATICTYPES !
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var hash = new HashMap[Int, String]
STATICTYPES !
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var hash = new HashMap[Int, String]
STATICTYPES !
hash = Hash.newhash = 3
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var hash = new HashMap[Int, String]
STATICTYPES !
hash = Hash.newhash = 3
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var hash = new HashMap[Int, String]
STATICTYPES !Scala
2Ruby
2hash = Hash.newhash = 3
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PATTERN MATCHING
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PATTERN MATCHING
def matchTest(x: Any): Any = x match { case 1 => "one" case "two" => 2 case y: Int => "scala.Int" case 2 :: tail => tail}
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gem install case
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gem install case
require 'case'
def matchTest x case x when 1 "one" when "two" 2 when Case::All[Integer] "ruby.Integer" when Case::Array[2, Case::Any] x[1..-1] endend
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gem install case
require 'case'
def matchTest x case x when 1 "one" when "two" 2 when Case::All[Integer] "ruby.Integer" when Case::Array[2, Case::Any] x[1..-1] endend
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gem install case
require 'case'
def matchTest x case x when 1 "one" when "two" 2 when Case::All[Integer] "ruby.Integer" when Case::Array[2, Case::Any] x[1..-1] endend
Scala3
Ruby2
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MONKEY PATCHING
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puts "a".to_s # => a
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puts "a".to_s # => a
class String def to_s "Monkey !" end def my_method "Patch !" endend
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puts "a".to_s # => a
class String def to_s "Monkey !" end def my_method "Patch !" endend
puts "a".to_s # => Monkey !
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puts "a".to_s # => a
class String def to_s "Monkey !" end def my_method "Patch !" endend
puts "a".to_s # => Monkey !
puts "a".my_method # => Patch !
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Implicit !
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class MySuperString(original: String) { def myMethod = "Patch !"}
Implicit !
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class MySuperString(original: String) { def myMethod = "Patch !"}
Implicit !
implicit def string2super(x: String) = new MySuperString(x)
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class MySuperString(original: String) { def myMethod = "Patch !"}
Implicit !
println("a".myMethod) // => Patch !
implicit def string2super(x: String) = new MySuperString(x)
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class MySuperString(original: String) { def myMethod = "Patch !"}
Implicit !
println("a".myMethod) // => Patch !
implicit def string2super(x: String) = new MySuperString(x)
Scala3
Ruby3
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Dynamic calls
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class Animal def method_missing name, *args if args.empty? puts "Animal says " + name.to_s else puts "Animal wants to " + name.to_s + args.join(", ") end self end end
Dynamic calls
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class Animal def method_missing name, *args if args.empty? puts "Animal says " + name.to_s else puts "Animal wants to " + name.to_s + args.join(", ") end self end end
Dynamic calls
animal = Animal.new
animal.qualk # => Animal says : qualks !animal.say("hello") # => Animal wants to say hello
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Scala 2.9
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class Animal extends Dynamic { def _select_(name: String) = println("Animal says " + name)
def _invoke_(name: String, args: Any*) = { println("Animal wants to " + name + args.mkString(", ")) this } }
Scala 2.9
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class Animal extends Dynamic { def _select_(name: String) = println("Animal says " + name)
def _invoke_(name: String, args: Any*) = { println("Animal wants to " + name + args.mkString(", ")) this } }
val animal = new Animalanimal.qualk // => Animal says qualkanimal.say("hello") // => Animal wants to say hello
Scala 2.9
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class Animal extends Dynamic { def _select_(name: String) = println("Animal says " + name)
def _invoke_(name: String, args: Any*) = { println("Animal wants to " + name + args.mkString(", ")) this } }
val animal = new Animalanimal.qualk // => Animal says qualkanimal.say("hello") // => Animal wants to say hello
Scala 2.9
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class Animal extends Dynamic { def _select_(name: String) = println("Animal says " + name)
def _invoke_(name: String, args: Any*) = { println("Animal wants to " + name + args.mkString(", ")) this } }
val animal = new Animalanimal.qualk // => Animal says qualkanimal.say("hello") // => Animal wants to say hello
Scala 2.9
Scala4
Ruby4
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Traits !
trait PimpMyClass { def myMethod = println("myMethod")}
class IncludeTrait extends PimpMyClass
(new IncludeTrait).myMethod
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Traits !
trait PimpMyClass { def myMethod = println("myMethod")}
class IncludeTrait extends PimpMyClass
(new IncludeTrait).myMethod
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Modules !module PimpMyClass def my_method puts "my_method" endend
class IncludeModule include PimpMyClassend
IncludeModule.new.my_method
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Modules !module PimpMyClass def my_method puts "my_method" endend
class IncludeModule include PimpMyClassend
IncludeModule.new.my_method
Scala5
Ruby5
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DUCK TYPING
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DUCK TYPING
It quacks !
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DUCK TYPING
It quacks !
It walks !
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DUCK TYPING
It quacks !
It walks !
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class Duck def quack; end def walk; endend
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class Duck def quack; end def walk; endend
class Platypus def quack; end def walk; endend
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class Duck def quack; end def walk; endend
class Platypus def quack; end def walk; endend
def act_as_a_duck animal animal.quack animal.walkend
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class Duck def quack; end def walk; endend
class Platypus def quack; end def walk; endend
def act_as_a_duck animal animal.quack animal.walkend
duck = Duck.newplatypus = Platypus.new
act_as_a_duck(duck)act_as_a_duck(platypus)
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class Duck { def quack = ... def walk = ...}
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class Duck { def quack = ... def walk = ...}
class Platypus { def quack = ... def walk = ...}
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class Duck { def quack = ... def walk = ...}
class Platypus { def quack = ... def walk = ...}
def ActAsADuck(a: { def quack; def walk })= { a.quack a.walk}
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class Duck { def quack = ... def walk = ...}
class Platypus { def quack = ... def walk = ...}
def ActAsADuck(a: { def quack; def walk })= { a.quack a.walk} val duck = new Duck
val platypus = new Platypus
ActAsADuck(duck)ActAsADuck(platypus)
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class Duck { def quack = ... def walk = ...}
class Platypus { def quack = ... def walk = ...}
def ActAsADuck(a: { def quack; def walk })= { a.quack a.walk} val duck = new Duck
val platypus = new Platypus
ActAsADuck(duck)ActAsADuck(platypus)
Scala6
Ruby6
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≃33
Only learn the syntax≃
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LET’S FRAMEWORKISE
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rSpec
Test::Unit
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UNIT TESTING
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UNIT TESTING
test "my test" do array = [1, 2, 3] assert_equal 1, array.firstend
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UNIT TESTING
test "my test" do array = [1, 2, 3] assert_equal 1, array.firstend
@Test def myTest() { val array = List(1, 2, 3) assert(array(0) === 1)}
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SPEC TESTING
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SPEC TESTING
describe "Get of Array" do it "first returns the first element" do array = [1, 2, 3] array.first.should == 1 endend
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SPEC TESTING
describe "Get of Array" do it "first returns the first element" do array = [1, 2, 3] array.first.should == 1 endend
describe("Get of List") { it("(0) returns the first element") { val array = List(1, 2, 3) array(0) should be 1 }}
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BDD TESTING
Feature: The user can get an element off an array Scenario: first is invoked on the array Given a non-empty array When first is invoked on the array Then the first element should be returned
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BDD TESTING
Feature: The user can get an element off an array Scenario: first is invoked on the array Given a non-empty array When first is invoked on the array Then the first element should be returned
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rSpec
Test::Unit
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rSpec
Test::Unit
Scala7
Ruby7
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24 000gems
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gems
12 000for Rails
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gems
12 000for Rails
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gems
12 000for Rails
Scala7
Ruby8
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Actors in Ruby ?
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Don’t try this at home !
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Don’t try this at home !
Scala8
Ruby8
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LET’S DEPLOY
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rails new myappheroku create myappgit push heroku master
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rails new myappheroku create myappgit push heroku master
http://myapp.heroku.com
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rails new myappheroku create myappgit push heroku master
Scala8
Ruby9
http://myapp.heroku.com
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2,07
39,74
70,74
Source : http://shootout.alioth.debian.org
Average performance(less is better)
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60
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2,07
39,74
70,74
Scala JRuby Ruby 1.9
Source : http://shootout.alioth.debian.org
Average performance(less is better)
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70,74
Scala JRuby Ruby 1.9
Source : http://shootout.alioth.debian.org
Average performance(less is better)
Scala9
Ruby9
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Do not talk of Ruby
to an admin49
Do not talk of Ruby
to an adminNeither of Java
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LET’S MEET PEOPLE
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«Most Java Programmers are Morons»
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«Most Java Programmers are Morons»
© Rails community
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Scala9
Ruby9
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