From: walter@...
Date: 2003-06-09T00:55:44+09:00
Subject: run-time type evaluation and programming style

Hi everyone,

I have been using Ruby for a couple of months now and have done 
several simple utilities in it, and quite frankly I love it.  Last 
week I wrote a simple Object persistence manager that would let me do 
simple crud to a db (apparently this is quite popular lately).  One 
of the features it does have is that I encode the expected type of 
the data going to and from the database.  I do this through the use 
of converter objects.  I find that I need to use .class method to 
determine the type of object that I am dealing with, in a case 
statement, and then do what I need to based on that.  Most any time 
that I need to use RTTI in Java it is almost certainly a violation of 
the Open/Closed principle (OCP) for that method.  But having said 
that by using method overloading in essence I am doing  the same 
thing, I am using RTTI to overload the method, but the Java language 
is doing it implicitly, in Ruby I need to do this via direct 
evaluation inside of a method.

I guess what I am asking is this considered generally acceptable in 
Ruby, in Java it would not normally be.  I am missing a better way to 
accomplish this.


Thanks,


Walt
*****************************************************
Walter Szewelanczyk
IS Director
M.W. Sewall & CO.        email : walter@mwsewall.com     
259 Front St.            Phone : (207) 442-7994 x 128
Bath, ME 04530           Fax   : (207) 443-6284
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