Hey,

"(btw. what os are you using?)" ...I am using windows xp. But the way I am working on this is, I connect to a secure shell network, using putty, and I am connect using an IP address of a linux machine. Now, is there any way I could work on this using windows itself?

Thanks,
Vidhi.



-----Original Message-----
From: Brian Schr?der [mailto:ruby / brian-schroeder.de] 
Sent: Friday, February 11, 2005 10:00 AM
To: ruby-talk ML
Subject: Re: new to this language

On Sat, 12 Feb 2005 02:46:52 +0900
"Ghelani, Vidhi" <vidhi.ghelani / intel.com> wrote:

> Hey ,
> 
> How do I get IRB?? How is this different from using SSH ?

chances are good it is installed together with the ruby interpreter. Just try to enter irb at the command line. (btw. what os are you using?)

It has got nothing to do with ssh. I'll show you a typical irb session:

---
bschroed@black:~$ irb
irb(main):001:0> 1+5
=> 6
irb(main):002:0> 3.times do puts "welcome to ruby" end
welcome to ruby
welcome to ruby
welcome to ruby
=> 3
irb(main):003:0> require 'complex'
=> true
irb(main):004:0> I = Complex.new(0, 1)
=> Complex(0, 1)
irb(main):005:0> 12 + I
=> Complex(12, 1)
irb(main):006:0> (12 + I) * (2 - I)
=> Complex(25, -10)
irb(main):007:0> exit
bschroed@black:~$ 
---

> 
> Also, can I have different classes in a file, that are not subclasses of one another? Using your example, could I have a class in that file that was not a subclass of Greet?

Yes you can. Seems it was not such a good example.

I recommend:
http://www.ruby-doc.org/docs/ProgrammingRuby/
http://www.ruby-doc.org/docbar/

and buy the dead tree version of the pickaxe second edition.

regards,

Brian

> 
> Thanks,
> Vidhi.
> 



> 
> -----Original Message-----
> From: Brian Schr?der [mailto:ruby / brian-schroeder.de] 
> Sent: Friday, February 11, 2005 9:37 AM
> To: ruby-talk ML
> Subject: Re: new to this language
> 
> On Sat, 12 Feb 2005 02:15:18 +0900
> Jim Menard <jimm / io.com> wrote:
> 
> > Vidhi,
> > 
> > Welcome to Ruby.
> > 
> > > 1) Just like in C++ you have a .h and a .cpp file , In this language how
> > > would you store your file. In other words if I open emacs and want to
> > > write a very simple small class in what format would I save this file ?
> > 
> > You store all your code in .rb files. There is no separate header file. You 
> > declare and define a class in one place, just like in Java. (That's not 
> > strictly true; in Ruby you can "re-open" a class and add more methods later. 
> > Don't worry about that yet.)
> > 
> > superclass.rb:
> > 
> > 	class Superclass
> > 		attr_accessor :super_instance_var
> > 		def initialize
> > 			@super_instance_var = 42
> > 		end
> > 	end
> > 
> > myclass.rb
> > 
> > 	require 'superclass'
> > 
> > 	class MyClass < Superclass
> > 		attr_accessor :my_instance_var
> > 		def initialize
> > 			@my_instance_var = 'hello'
> > 		end
> > 	end
> > 
> > another.rb
> > 
> > 	require 'myclass'
> > 
> > 	mc = MyClass.new
> > 	puts mc.my_instance_var
> > 	puts mc.super_instance_var
> > 
> > > 2) How do you compile your code? What is the syntax?
> > 
> > Ruby is an interpreted language, which means that it doesn't need to be 
> > compiled before you run it. To run "another.rb" above, type
> > 
> > 	ruby another.rb
> > 
> > > 3) Do you need a main and a makefile ? I am sure you would need a main
> > > to test it . If yes how do you save the main? In what format?
> > 
> > You don't need a main method. All Ruby code is executed as it is seen by the 
> > interpreter. Some of the code above (superclass.rb and myclass.rb) define 
> > classes and some of the code (another.rb) creates an instance of a class and 
> > prints some output.
> > 
> 
> one thing I want to add, is that you need not create a seperate file per class. You can as well group classes by functionality and put multiple classes in one file. (I think using one file per class is a java idiom).
> 
> 
> first.rb
> class Greet
>   def initialize(name)
>     @name = name
>   end
> end
> 
> class GreetEnglish < Greet
>   def greetme
>     puts "Hello #{name}"
>   end
> end
> 
> class GreetGerman < Greet
>   def greetme
>     puts "Hallo #{name}"
>   end
> end
> 
> class GreetSpanish < Greet
>   def greetme
>     puts "Hola #{name}"
>   end
> end
> 
> greeters = [GreetEnglish, GreetGerman, GreetSpanish]
> greeter = greeters[rand(greeters.length)].new
> greeter.greet
> 
> is perfectly reasonable and allowed. (Though maybe not two good design, and you can shorten this alot when you have learned about dynamic programming).
> 
> And additionally, if you want to play with the language use irb, the ruby interactive shell.
> 
> good luck and enjoy ruby,
> 
> Brian
> 
>