Ruby: EventMachine not loading

UPDATE:

I found the simple answer and it's completely my own fault: I stored the above code in a file called "eventmachine.rb". Thus when I required 'eventmachine' it just imported the same file, which does not contain a definition for EventMachine.

So this is not really a post about EventMachine.

ORIGINAL POST:

Excuse me, but what's going on?

require 'rubygems'
require 'eventmachine'

EventMachine

gives

uninitialized constant EventMachine

in both TextMate and on the console when I run "ruby myfile.rb".

But if I type the same thing into IRB, I get

=> EventMachine

开发者_如何学Go

.

...

I got so frustrated that I followed the rash instructions on http://blog.carlmercier.com/2007/12/14/how-to-fix-that-rubygems-mess-on-leopard/ -- wiping out my Ruby and Rubygems environments and reinstalling them from MacPorts. IRB still works and TextMate/commandline still fails in the same way. I even reduced my TextMate PATH to the one place where Ruby, Gem, and IRB are installed now: /opt/local/bin -- which is what Which reports.

Finally, when I

puts Gem.path

on either IRB, TextMate, or the console, I get the same path.

---

I found the simple answer and it's completely my own fault: I stored the above code in a file called "eventmachine.rb". Thus when I required 'eventmachine' it just imported the same file, which does not contain a definition for EventMachine.

---

Have you installed the gem?

gem install eventmachine

Typically an error like that in the code you show is because the line

require 'eventmachine'

failed and that class/module constant, EventMachine, is not defined.

Also, if you are running ruby 1.9, you no longer need to have

require 'rubygems'

---

I don't understand why the message is "Uninitialized Constant", but the problem is that you provided nothing to run. I get the same error with your code, but if I change it to:

EventMachine::run{
   EventMachine::add_periodic_timer( 0.1) { 
    print '.'
   }
}

then it works exactly as I expect - it prints 10 dots per second.