From: Sebastian Hungerecker <sepp2k@...>
Date: 2009-08-19T11:34:15+09:00
Subject: Re: if defined on var

Am Mittwoch 19 August 2009 04:22:18 schrieb Derek Smith:
> My goal is to see if a table exists by testing the var holding the data
> is true/defined or not.  Will you help?

true and defined are two very different things. Take this snippet as an 
example:

x = 42
y = false
z = nil

Here the variables x, y and z are defined. The variables a, b and foobarbaz 
are not. In short: once you assign a value to a variable that variable is 
defined - no matter whether that value was true or not. If you want to check 
whether the value a variable holds is true or not, do that. Don't use 
defined?.
In your case you can just do  if table_exists  which even reads more 
naturally.

HTH,
Sebastian