From: Martin DeMello <martindemello@...>
Date: 2003-01-18T07:28:33+09:00
Subject: Re: quick: it responds, it evaluates, and is not empty

ahoward <ahoward@fsl.noaa.gov> wrote:
> On Sat, 18 Jan 2003, Tom Sawyer wrote:
> 
>> but this does not free one from using respond_to? i.e. instead of: if
>> respond_to?(:x), one would simply say: if x != nack.
> 
> i see your point, but see my post to david.  in general i love syntax
> shortcuts, but i'm not comfortable about that because it hide exception
> throwing...

The point, though, is to return a nack *instead of* throwing an
exception. For speed, if nothing else.

<snip NackClass>

> i actually like that one (someone suggested it earlier).  it's short and
> ignores exceptions, but it would be patently clear to anyone reading the code
> that missing methods do not throw exceptions.

That was mine. The problem, though, is that anyone writing their own
method_missing has to explicitly remember to call super. I know it'd
break Ruby's model, but there are times I think it'd be really
convenient if method_missing was treated as a special case, and behaved
more like, say, a multimethod.

martin