From: Edward Faulkner <ef@...>
Date: 2006-02-14T03:56:14+09:00
Subject: Re: tree structures

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On Tue, Feb 14, 2006 at 03:13:25AM +0900, frank wrote:
> But it seems like there is a huge gulf between my procedural
> thinking and an OO thinking with regard to this tree structure.  How
> would you represent a linked list in Ruby?

Why do you really want a "linked list"?  Just use an Array and stop
worrying about how it's implemented.  This is an example of thinking
too low-level.

But more importantly, why use lists at all to represent a tree?  Why
not just build a tree?  Trees are recursive.  Your data structure
isn't.  No wonder the code to navigate it is complicated.  I would go
farther and say that your parser should probably be recursive too.

Your problem is not with "OO" vs "procedural" thinking.  I'd say it's
more "low-level abstractions" vs "high-level abstractions". =20

And even if this code was translated to C, I'd still consider it
wrong, because you've chosen the wrong structures.  It's just that
Ruby is such a clear languages it makes bad choices more painfully
obvious.

Learning to think recursively isn't easy, but it's incredibly valuable
for solving problems like this.

best regards,
Ed

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