Learn Ruby on Rails

1
Ruby
Language

• Session 1

2
Websites built on Rails

• Twitter
• Basecamp
• Hulu
• SlideShare
• GitHub
• Shopify
• Groupon
• AirBnb

3
What is Ruby ?

• A dynamic, open source programming language with
  a focus on simplicity and productivity. It has an
  elegant syntax that is natural to read and easy
  to write.
• - https//www.ruby-lang.org
• It was developed by Yukihiro Matsumoto (also
  known as Matz in the Ruby community) in the mid
  1990s in Japan.
• It is a pure Object-Oriented and an interpreted
  scripting language.

4
Say WHAAAAT ? OOP vs FP

• According to Wikipedia, OOP is a programming
  paradigm is based on the concept of objects,
  which may contain data, in the form of fields,
  often known as attributes and code, in the form
  of procedures, often known as methods.
• Functional programming is the form of programming
  that attempts to avoid changing state and mutable
  data.

5
Interpreted vs Compiled

• Ruby is an interpreted scripting language and is
  run directly without first compiling and
  generating the byte code.
• With a compiled language, code you enter is
  reduced to a set of machine-specific instructions
  before being saved as an executable file.
• Interpreted programs can modify themselves by
  adding or changing functions at runtime. It is
  also usually easier to develop applications in an
  interpreted environment because you don't have to
  recompile your application each time you want to
  test a small section.

6
Colour me curious. Installation

• Windows RubyInstaller
• Ubuntu Package manager
• Mac Pre Installed !!!

7
Lets compare shall we

• Imagine you want to get the time one month from
  this very second. Here is how you would do that
  in Python and Ruby languages
• Python
• from datetime import datetime
• from dateutil.relativedelta import relativedelta
• new_time datetime.now() relativedelta(months1
  )

8
And in Ruby...

• Ruby
• require 'active_support/all'
• new_time 1.month.from_now

9
Let the magic begin

• Ruby files have .rb as extension
• Hello World
• Classes and Object
• Global variable
• Instance variable
• Class variable

10
Ruby basics

• Array
• Hash
• Range
• If..Else Case
• Loops
• Methods

11
Thank You,

Keep Learning.

• Space-O Technologies