From: gabriele renzi <surrender_it@...1.vip.ukl.yahoo.com>
Date: 2004-06-06T21:03:43+09:00
Subject: Re: How to ducktype a Hash?

il Sun, 6 Jun 2004 18:52:44 +0900, Jeff Mitchell
<quixoticsycophant@yahoo.com> ha scritto::


>This is the fault of PStore or of the lack of agreed-upon semantics
>for classes with hash-like behavior.  There should be a standard list
>which includes the definition of such behavior.  Here, I'll start the
>list now:
>
> hash-like:  #fetch, #store
>array-like:  #at, #store
>
>Any others?  How about tree-like?
>
>I want this list to be part of the ruby standard -- clearly
>documented so that implementers know they should define #fetch
>and #store for the hash-like classes they write.  [] should
>be viewed as convenience only.

I may be wrong but what you're asking has been throw out many times. 
It would be wonderful to have stuff like this for everything,
toghether with a possible mix-in. 
We have, actually, many 'default quacks' like :read and :write for
IOs, :each for enumerables,  and so on.

 Maybe adding some more mix-ins would be fine for many people's need
(say, if a Map mixin existed, we could have it rely on fetch(),keys()
and store() to provide all the other methods). This way hash-like
stuff like PStore, will just need to include the mix-in and Sean could
just check for kind_of? Map if he feels the need for this.  

Oh, and can I ask for an Input and Output mixin, while I'm at it ? :)