How can I use a variable in another file on Ruby on Rails?

Question

I'm trying to use my variable in all files of my program. this is an example of what I'm trying to do.

 main.rb
 Class1
 def self.test1
 puts "class 1" if @@debug
  end
 end
 @@ debug = true

 class.test1
 class.test2

 class2.rb
 Class2
 def self.test2
 puts "test2" if @@debug
  end
 end

I really hope it's enough clear for the community, any help would be appreciated, thanks!

Linuxios · Accepted Answer · 2012-07-03 13:56:08Z

2

You want a global variable or constant. You could create your own, but Ruby conveniently comes with a builtin $DEBUG global variable. When you specify the -d option to ruby, $DEBUG will be true, and otherwise, false.

If the classes are in multiple files, put this in the file that includes the others:

DEBUG=$DEBUG

And in the other files, use DEBUG for debug, rather than $DEBUG.

edited Jul 3, 2012 at 13:56

answered Jul 3, 2012 at 13:46

Linuxios

35.9k13 gold badges96 silver badges118 bronze badges

Sign up to request clarification or add additional context in comments.

9 Comments

Takezo Shinmen Over a year ago

i want a global variable but in the other file it doesn't work --"

Linuxios Over a year ago

@TakezoShinmen: And how are you connecting these files? Require? Nothing will work without require.

Linuxios Over a year ago

@TakezoShinmen: Show me the require.

Patrick Oscity Over a year ago

Maybe it is not clear enough, that you do not need to build your own debug mechanism. simply check for $DEBUG and run your program with ruby -d prog.rb when you want the debug output and with ruby prog.rb when you don't want it. No need for class variables etc.

Takezo Shinmen Over a year ago

@Linuxios these are my require: require 'qark_stat',require 'qark_matrix' padde i have to create $DEBUG and only type -d for using it ?

|

sohaibbbhatti · Accepted Answer · 2012-07-03 13:46:58Z

1

You can create a getter method to get class_variable

def self.get_debug
  @@debug
end

rails however provides a method called cattr_accessor http://apidock.com/rails/Class/cattr_accessor This will allow you to set and get the class variable outside the class

i.e. Class1.debug = false

answered Jul 3, 2012 at 13:46

sohaibbbhatti

2,68224 silver badges21 bronze badges

1 Comment

Takezo Shinmen Over a year ago

,I try it but i have an undifined method :s

Collectives™ on Stack Overflow

How can I use a variable in another file on Ruby on Rails?

2 Answers 2

9 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

9 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related