Simple ruby syntax question [duplicate]

This question already has answers here开发者_JS百科: Closed 11 years ago.

Possible Duplicate:

What is Ruby's double-colon (::) all about?

Can you explain me, what two dots :: in ruby means?

Explain me on this example:

AWS::S3::Bucket.find(BUCKET).objects  

What is here ASW, what S3, and what is Bucket (I mean, classes, packets, objects,...)

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Here is the exact code that you are using under the hood:

https://github.com/marcel/aws-s3/blob/master/lib/aws/s3/bucket.rb

As you can see, there are nested modules/classes:

module AWS
  module S3
     class Bucket < Base
     end
  end
end

So:

• AWS is a module.
• S3 is a module.
• Bucket is a class.

The class Bucket is nested inside the module S3 which is nested inside the module AWS.

A Module is basically a bundle of methods/constants, but they differ from classes in the sense where they can't have instances. You use that a lot in order to refactor your code and to better design it. More information on Modules here.

The :: is used to refer to the nested modules/classes. It's a kind of resolution operator, that helps you reach your nested modules/classes/constants by knowing their paths.

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It's a ruby module. A module is a container of classes, and it's used to separate the namespace, it's similar (in a way) to java packages.