From: Gavin Sinclair <gsinclair@...>
Date: 2004-02-01T23:21:52+09:00
Subject: Re: check whether a class is defined, listing all classes

On Monday, February 2, 2004, 12:52:30 AM, David wrote:

> Robert Klemme wrote:
>>>But what if the class name to be checked is a string?
>>>("Test::Unit::TestCase")?
>> 
>> irb(main):005:0> eval "defined? " + "Test::Unit::TestCase"
>> => nil
>> irb(main):006:0> require 'test/unit/testcase'
>> => true
>> irb(main):007:0> eval "defined? " + "Test::Unit::TestCase"
>> => "constant"

> Hm, I should've added that I didn't want to involve 'eval'. But then why
> not, I'll just need to check the input using a simple regexp. After all,
> almost everything in Ruby (require, load, irb, class_eval) is using eval
> anyway...

Take a look at StandardClassExtensions on the Wiki.  There's something
in there just for you :)

Cheers,
Gavin