Ruby

1) Installation of Ruby 

http://rubyinstaller.org/


2) After installation-->in windows
  > Run cmd
 

3) To check the version

  > ruby -v


4)

Interactive Ruby (IRb):

Just type irb at your command prompt and an Interactive Ruby Session will start as given below:

$irb
irb 0.6.1(99/09/16)
irb(main):001:0> def hello
irb(main):002:1> out = "Hello World"
irb(main):003:1> puts out
irb(main):004:1> end
nil
irb(main):005:0> hello
Hello World
nil
irb(main):006:0>

---------------------------------------------------------------------------------------------------------------

Ruby Global Variables:  $

Global variables begin with $. Uninitialized global variables have the value nil

Ruby Instance Variables:  @ 

Instance variables begin with @

Ruby Class Variables:  @@

Class variables begin with @@ and must be initialized before they can be used in method definitions.

Referencing an uninitialized class variable produces an error.

------------------------------------------------------------------------------------------------------

class Student

   @@no_of_students=0

   def initialize(id,name,addr)

     @stu_id=id

     @stu_name=name

     @stud_add=addr

    end  

def display()

 puts "student  #@stud_id  #@stu_name  #@stud_add" 

end

end

stu1=Student.new("1","sree","IN")

stu2=Student.new("2","sahi","US")

stu1.display()

stu2.display()

-------------------------------------------------------------

> ruby sahi.rb

----------------------------------------------------------------------------------------------------------