From: Shadowfirebird <shadowfirebird@...>
Date: 2008-07-31T00:24:30+09:00
Subject: Re: How to do methodsoverloading in

I must admit that I love Ruby because it manages to combine brevity
with readability (quite a trick!).

But the brevity sort of goes out the window if every method has to
paranoidly check the class of every parameter passed to it. It's a bit
of a pain.  But so is the alternative.

I gather from what David says that there's no magic bullet...?



On Wed, Jul 30, 2008 at 3:46 PM, David A. Black <dblack@rubypal.com> wrote:
> Hi --
>
> On Wed, 30 Jul 2008, Shadowfirebird wrote:
>
>>>> Given that Ruby is typeless, I'm not sure how it would be otherwise.
>>>
>>> Ruby is strongly typed, dynamic, and extensible, permitting Monkey
>>> Patching.
>>
>>
>> Okay, *there* you caught me.  I was grossly oversimplifying.
>
> Not grossly :-) Type in Ruby is kind of a tautology: an object's type
> is the type "the type of objects which are of this type." In the end,
> the notion of type kind of cancels itself out (or gets replaced by the
> notion of class, which it doesn't actually correspond to and which
> causes a lot of problems).
>
>> What I should have said was, Ruby isn't *statically* typed.  Which
>> means that it can't use a parameter signature to tell different method
>> definitions with the same name apart.  At least, so I understand is
>> the received wisdom -- I imagine only Matz could say for sure.
>
> People have written lots of libraries that try to examine method
> signatures, if not statically, then dynamically but in such a way that
> things will fail if the method is called with the wrong arguments.
> "Wrong," however, is almost always defined as "of the 'wrong' class",
> which of course doesn't play very nicely with the fact that Ruby
> objects have more on their minds than what class gave birth to them.
>
> There have been more elaborate attempts to check for type, rather than
> class, and some have been very interesting and educational; but they
> always end up feeling like a kind of second skin on top of what Ruby
> already does.
>
>
> David
>
> --
> Rails training from David A. Black and Ruby Power and Light:
>  *  Advancing With Rails    August 18-21    Edison, NJ
>  * Co-taught by D.A. Black and Erik Kastner
> See http://www.rubypal.com for details and updates!
>
>



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Me, I imagine places that I have never seen / The colored lights in
fountains, blue and green / And I imagine places that I will never go
/ Behind these clouds that hang here dark and low
But it's there when I'm holding you / There when I'm sleeping too /
There when there's nothing left of me / Hanging out behind the
burned-out factories / Out of reach but leading me / Into the
beautiful sea