From: "David A. Black" <dblack@...>
Date: 2009-07-14T22:05:30+09:00
Subject: Re: Twelve rules of Ruby

Hi --

On Tue, 14 Jul 2009, Panu Kinnari wrote:

> Scott Adams of Dilbert fame talked about learning twelve concepts of
> something and in the progress become more knowledgeable about given
> subject than most of the other people.
>
> Original blogpost here: http://www.dilbert.com/blog/entry/rule_of_twelve
> And followup with actual example:
> http://www.dilbert.com/blog/entry/twelve_rules_of_energy_efficient_building/
>
> Question I am proposing is found in subject line, what would be The
> Twelve Rules for Ruby.
>
> I am not that great programmer and one of the reasons for starting this
> thread is to give some direction to my learning. And then to write more
> code to actually learn.
>
> I am not expecting for everyone to post 12 things, but maybe few that
> they think should be included on this kind of list.

Here's half a dozen. I would say that if everyone understood these
principles, and really stopped to think about them when puzzled by
something that Ruby was doing, or something that wasn't working in
their code, it would make a huge difference overall to people's
experiences learning and using Ruby:

1. Classes are objects.
2. Objects don't "have" methods; they have the intelligence to resolve
    messages by looking for methods along their class/module lookup
    path.
3. Every instance variable you ever see in any Ruby program belongs to
    whatever object "self" is at that moment, without exception. (Which
    is one reason that understanding how "self" gets assigned is
    absolutely vital.)
4. A code block is a syntactic construct, not an object. 
5. Class variables are not class variables, in the sense of belonging
    to a particular class. They are class hierarchy variables. 
6. Inheritance (A < B) is not the same as, and not related to, nesting
    (A::B).

The first one on the list, alone, is worth the price of admission :-)


David

-- 
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