This document provides an overview of the Ruby programming language, including: - Ruby was influenced by Perl and created in 1993 by Yukihiro Matsumoto to have more scripting power than Perl and be more object-oriented than Python. - Ruby is truly object-oriented, portable, has garbage collection, exception handling, and a syntactically simple design. - Everything in Ruby is an object, including properties and actions, and there is no difference between expressions and statements. - Ruby is very flexible, allowing users to freely alter its parts with open classes and the ability to change built-in methods and core classes.

1. Ruby
Programming == Joy
Krupa Suthar

2. Why named ‘Ruby’?
● Influenced by majorly - Perl
● July Birthstone

3. Idea behind Ruby
● Yukihiro Matsumoto(‘Matz’) and a colleague were discussing of creating language
with more scripting power than Perl and more object-oriented than Python
● Born in 1993
● Features
○ Truly Object-Oriented
○ Portable
○ Garbage Collector
○ Exception handling
○ Syntactically simple

4. Get started with Ruby
● Version Manager - rbenv, rvm
● Install
● Irb - Interactive Ruby shell

5. Is this Object?

6. Is this Object?

7. Everything is OBJECT
● Including their properties and actions
● Everything has value, even if that value is nil
● No difference between an expression and statement
● =, .. , &&, ||, or, ::

9. Ruby’s Flexibility
● Allow user to freely alter its parts
● No restrictions
● Open classes
● Ability to change any inbuilt methods
● Ability to change core classes like Fixnum

11. Blocks - Truly expressive
● Add closure to method and closure will tell method how to act
● Invoke with yield
● block_given?
● Block with variables

13. Ruby and Mixin
● Ruby does not support multiple inheritance
● Mixins allows to achieve by requiring multiple modules
● Modules - Collection of methods, constants, other module and class definitions
● Class can access modules by requiring

15. Ruby’s visual appearance
● Code readable like story
● Simple naming conventions
○ snake_case - Method name
○ CamelCase - Class name
○ @var - Instance variable
○ var - Local variable
○ $var - Global variable

16. Things you need to know about Ruby
nil and false
● Everything except nil and false is considered true
● In Java and some other languages, 0 and possibly other values such as empty list,
are considered false
Access Modifiers
● Modifiers
● Scopes

17. Expressive method names
● Methods answering question return with Question mark (?)
E.g. Array#empty?
● ‘Dangerous’ methods end with Exclamation mark (!)
E.g. save!
Singleton methods
● Per-object methods. They are only available on the Object you defined it on.

19. Message passing, not function calls
● A method call is really a message to another object
Keyword arguments
● Like Python, Ruby also allows to use keyword as argument
Missing methods
● missing_method error
● NameError

21. RubyGems
● What are Gems?
● Installing Gem
● Bundler
● Using Gems

22. Thank You !
Any Questions??