From: "F. Senault" <fred@...>
Date: 2008-05-29T17:49:56+09:00
Subject: Re: The duck's backside

Le 29 mai � 06:45, Eleanor McHugh a �crit :

> On 28 May 2008, at 23:23, Mark Wilden wrote:

>> That's true, but it wasn't my point. The question is whether all  
>> methods with the same name in all active classes should be  
>> semantically equivalent. I think that's a rather larger assumption  
>> than that Numeric means "numeric."
> 
> Numeric may well mean "numeric" in some particular sense, but that is  
> only a subset of all objects which may have a valid numeric  
> representation. As I said, you're applying a static typing mindset to  
> a place where it's not necessary and whilst Ruby will let you do that,  
> in the long term you'll find yourself doing much more work with very  
> little (if any) gain in software robustness. In fact if you're writing  
> a library you'll introduce additional fragility to code interfacing  
> with it because Ruby programmers generally expect Duck Typing and  
> write accordingly.

BTW, your code makes in fact two assumptions : 

- The object has a valid numeric value (via .to_i(nt) in your case),
- But also that the object has a _string_ representation that happens to 
    be that numeric value (via the #{} interpolation).
    
Wouldn't it be better to write this :

@post "first=#{a}&" + (b.nil? ?
                       "second=ignored&third=#{v.to_int}" : 
                       "second=#{v.to_int}&third=ignored")

> Ellie

Fred
-- 
Steps have been taken, a silent uproar     Has unleashed the dogs of war
You can't stop what has begun      Signed, sealed, they deliver oblivion
We all have a dark side, to say the least    And dealing in death is the
nature of the beast                            (Pink Floyd, Dogs of War)