From: Robert Klemme <bob.news@...>
Date: 2006-02-16T19:48:27+09:00
Subject: Re: Creating objects without knowing their names

Joel VanderWerf wrote:
> paul.p.carey@gmail.com wrote:
>> Hi
>>
>> I'd like to load an arbitary number of Ruby files from a directory
>> and create their associated objects. However, I don't know the class
>> names of the files that have just been loaded. Is it possible to
>> determine a file's class name once that file has been loaded?
>> (Without resorting to parsing, or enforcing a mapping between the
>> filename and class name.)

> You probably know this already, but for the benefit of bystanders:
> there isn't in general one-to-one mapping between classes and files.
> A class
> can be defined across several files; a file can contain several class
> definitions. (Maybe in the case of the files you are using there is
> always a 1-1 map, though.)

There are other options.  Some of them:

 - Make sure all classes on those files inherit a base class which
overrides #inherited so it gets notified every time a sub class is
created.  You can then store the set of sub classes in a member of the
base class and use that for whatever purposes.

 - Make classes in those files register with some arbitrary registry you
create (that's basically the same as the first just more explicit).

 - use set_trace_func to trance execution of those files and notice
whenever a new class occurs.  (Not sure whether that works though).

Kind regards

    robert