Re: class vrs. method

Hi --

On Sun, 7 Dec 2008, Tom Cloyd wrote:

> I've been thinking about this question for days, and have yet to come up with 
> a satisfactory answer. I have deep respect for the "smarts" available on this 
> list, so I'll toos the question out here. I've been programming in Ruby for 
> possibly a couple of years, learning what I need to know to get something 
> done, at the time I need to know it. I don't have much time for pure 
> Ruby-study, although I much wish I did. I'm presently writing database 
> program in ruby, using only ruby (no database engine), which will manage a 
> network of nodes (labels) and relationships (also labels). It's simple, but 
> potentially very powerful, and a great opportunity for me to push into new 
> territory with Ruby. It's coming along well, and I'm much enjoying the 
> experience.
>
> I'm getting it done by writing a number of methods. I keep looking at other 
> people's programming, and I see many, many classes. Some of these classes 
> look pointless to me. A mere method would have done the trick. Why a "class"? 
> I personally feel no need whatsoever to actually USE one. I'm getting 
> everything done easily and artfully with mere methods. I simply don't get it 
> - about classes. It looks like an elegant idea, and in more complex 
> programming I can imagine why one might use them, but...I've simply cannot 
> find a reason to bother.
>
> I've read a lot about them, but...here's my question:
>
> Am I missing something? Can anyone give me a compelling reason to write fewer 
> methods and more classes?
>
> If anyone's interested, the program to which I referred may be examined at
>
> http://tomcloyd.com/misc/setnet.txt
>
> (I had to change the file extension to txt, as 'rb' refused to load in my 
> browser, and might well do that in yours as well.)
>
> As I've puzzled about this for days, I'm very interested to see what better 
> informed people have to say about this question. Please understand that I do 
> grasp the basics, but do NOT see what the compelling reason is to use a class 
> in a reasonably simple program. Thanks!

I'll just add to the answers you've already received by saying:
remember that classes are not the whole story behind a more
object-oriented approach. Objects are :-) There are ways you can
engineer objects that don't necessarily use classes, but that do give
you the advantages of the kind of encapsulation and stylistic gains
that people have been talking about.

In particular, I'm thinking of modules, which can be used to add
functionality to a particular object as well as to all instances of a
particular class. And/or just defining one or more methods on a
particular object.


David

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