From: "David A. Black" <dblack@...>
Date: 2007-12-07T05:22:55+09:00
Subject: Re: Worth an RCR? static_type_check, polymorphic_type_check,

Hi --

On Fri, 7 Dec 2007, Stefan Rusterholz wrote:

> Robert Klemme wrote:
>> 2. point in time is not the only difference as you have pointed out
>> (method_missing).
>
> While I mostly agree with what you say: if somebody defines
> method_missing, he should update respond_to? accordingly. Anything else
> I'd consider a bug.

You might want to file a bug report against the standard library:

>> require 'ostruct'
=> true
>> os = OpenStruct.new
=> #<OpenStruct>
>> os.respond_to?(:"a=")
=> false
>> os.a = 1
=> 1

:-) I think it all depends on exactly what you're doing with
method_missing. In general, I tend to see it the other way around:
respond_to? tells you what the object's current knowledge of its
messages is, while method_missing is specifically a handler for
messages the object does *not* respond to. In the end, it can be done
either way, and probably should be, in different situations. I
wouldn't say that either approach is inherently buggy.


David

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