Hi,
I did not quite understand this :
In any file so the code in the if-block will be executed only if the
file is being run directly by the interpreter (e.g.: ruby
hello_world.rb)
So if I had a file hello_world.ruby and if I have the if block in it.
When I give the command ruby hello_world.ruby wont the entire file be
run? SO how does the if block help?
Sorry, but I think I am understanding it wrong.
Thanks,
Vidhi
···
-----Original Message-----
From: Joao Pedrosa [mailto:joaopedrosa@gmail.com]
Sent: Friday, February 11, 2005 9:36 AM
To: ruby-talk ML
Subject: Re: new to this language
Hi,
> 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.
Else, you can use
if __FILE__ == $0
p 'Hello World!'
end
In any file so the code in the if-block will be executed only if the
file is being run directly by the interpreter (e.g.: ruby
hello_world.rb). It's useful so you can have a file that behaves like
a library and a program, depending on how it's loaded. You load a
library with the require (or load) command (e.g.: require 'open-uri').
I like to use such capability to test one or another thing in a file
while I'm working on it.
Welcome to Ruby.
Cheers,
Joao