the ruby programming language - ryan farnell

The Ruby Programming Language

Ryan Farnell

1

History

• 1995

• July 2004 (Ruby on Rails)

2

pure object-orientated

3

What is an object?

4

1. The data an object contains is unique to itself

5

2. Only the object that contains the data can manipulate that data

6

one logical unit with data and functions grouped together

7

demo

8

basic data as objects

9

Value Type of Object

123 Fixnum

“Ruby” String

TRUE TrueClass

10

functions as objects

11

Value Type of Object

function Proc

12

blocks allow for the passing of a function as

a parameter

13

Ways to Use Blocks

• internal iterators

• resource allocation/deallocation

• changing functionality

14

demo

15

Conditionals

16

Ruby supports standard conditionals

17

Ruby also allows post conditions

18

Ruby uses the normal case/when statement as

in other languages

19

Ruby supports standard looping structures

20

internal iterators are often used in place of standard structures

21

demo

22

Classes

23

act as templates for the beginning functionality

of an object

24

class inheritance

25

a class can gain functionality (inherit) from other classes

26

all classes inherit from exactly one class

27

mixins can be used to add extra functionality

28

class gains all the methods in the mixin

29

Mixins

• Have access to all instance variables

• Have access to all private and public methods

30

demo

31

Ruby has some problems

32

Disadvantages• Slow Execution

• Problems with threading

• No specification

33

Virtual Machines• Ruby 1.9 YARV

• JRuby

• IronRuby

• Rubinius

• MacRuby

34

http://www.ruby-lang.org/en/downloads/

35

Books

• Programming Ruby 2nd Edition

• by Dave Thomas, Chad Fowler, and Andy Hunt

• Ruby From Novice to Professional

• Peter Cooper

36

Q & A

37

Metaprogramming

38

code that writes code

39

Ruby has many metaprogramming

hook

40

demo

41