From: Eric Mill <emill@...>
Date: 2006-09-01T03:15:28+09:00
Subject: Re: Ruby Books

That's being a little oversemantical.  Going into the details of Ruby's 
call chain and how method lookups work underneath the hood would totally 
defeat the intent of why's book, which is to welcome new blood and 
inspire curiosity as to how Ruby could possibly be as magic as why 
(accurately) portrays it.

To the inquiring soul, unlearning a simple conception about methods 
later is easier than learning a complex conception about methods now.  
And I don't even really agree that calling a method a verb is 
inaccurate.  It's poetry, like the rest of his book.

-- Eric Mill

Rick DeNatale wrote:
> On 8/31/06, Matt Todd <chiology@gmail.com> wrote:
>> Hi, I'm surprised nobody's mentioned it yet, but, _Why's Poignant
>> Guide to Ruby (http://www.poignantguide.net/) is an excellent, free,
>> trippy resource for going over the fundamentals of Ruby. It's not
>> finished yet, unfortunately, but it covers a great deal, and in a very
>> entertaining way, too. _Why's writing style is unique and quite
>> entertaining considering it's a programming book. If you can read
>> through it, it's a great way to get introduced to the language. It was
>> my first introduction to Ruby.
>
> I enjoy it,  but...
>
> I've got a few quibbles with some of why's terminology, which may lead
> the unaware off track.
>
> For example in the "Parts of speech chapter" which occurs fairly soon:
> http://www.poignantguide.net/ruby/chapter-3.html#section2 he says:
>
> "   front_door.open
>
>   In the above, open is the method. It is the action, the verb. "
>
> Well, open here isn't really a method, it's a name which is used to
> find a particular method.  It gets turned into the symbol :open, then
> a search is done for a method which is associated with that symbol,
> starting with the (singleton) class of the object referenced by
> front_door, and proceeding up the superclass chain.  So it's a verb,
> but it's not really an action, 'sit' is a verb, but it produces very
> different actions depending on whether it's said to a person, a dog, a
> robot, or something else.
>
> Now this might be getting into a little too much detail at this stage
> of an introduction to Ruby, but the lack of a separation between a
> method call, and the method itself troubles me.  The Pickaxe DOES make
> this distinction on the second page of the chapter which starts
> discussing Ruby programming.
>
> It might seem a minor point, but to my mind it's this separation which
> is the hallmark of object-orientation as Alan Kay first defined it,
> and Ruby practices it.  There doesn't seem to be an official Ruby name
> for the name of a requested method.  In Smalltalk we call it a message
> selector.
>
> The Pickaxe borrows terminology from Smalltalk, distinguishing
> messages and methods. Dave's use in the pickaxe might be considered
> informal by some,  but the RDoc hints at this as well.
>
>   * Object#method - "looks up the named method in obj"
>   * Object#method_missing - is "invoked by Ruby when obj is sent a
> message it cannot handle, and args are any arguments that were passed
> to it.
>   * Object#send - "invokes the method identified by symbol, passing
> it any arguments and block."
>
> It looks a lot like Smalltalk semantics to me.  The only real
> difference is that Smalltalk actually has a Message class which gets
> instantiated when it's needed, such as for the argument to the
> doesNotUnderstand: message which corresponds to Ruby's method_missing.
>