Re: [httpRange-14] What is an Information Resource?

(with apologies for the long vacation-induced delay in replying)

Pat Hayes wrote: 

> [Noah Mendelsohn wrote:]
> > That content type licenses the receiver to interpret the octets as 
> >more than characters, but as representing a tree of elements with some
> >semantics.
> Right, but note, REPRESENTING the tree. Not actually BEING the tree.

Let's say I have in mind a tree.  It is the tree that has a node labeled R 
as its root, A as a left child, and B as a right.

       |   |
       A   B

I mint as a URI and as the 
authority I decide that it identifies the tree above.  Are you saying I've 
made a mistake?

Let's say I further invent a media type, say tree/preorder, I define a 
lisp-like syntax in which every node is a triple of its label, it's left 
child and its right, set out as Unicode characters, space separated, in 
parens.  So, the above tree can be "represented" using that media type as:

        (R (A () ()) (B () ())) 

It doesn't much matter what representation I choose.  All that matters is 
that it's a media type that can represent trees.

If you do an HTTP get to my URI, I return a 200 with that media type and 

The URI identifies the tree.  It's information in the Shannon sense.  Of 
all the possible trees, I can use a message to help you tell which one I 
have in mind.  Or, if you like, of all possible information resources, 
only some of which are trees, the combination of the 200, the media type 
tree/preorder, and the LISP-like string above tell you which information 
resource I have in mind, I.e. the abstract tree.  Anything broken with 


P.S. I currently own but for the record I prefer not to 
actually assign the sample URI above.  You'll get a 404 if you try to 
access it. 

Noah Mendelsohn 
IBM Corporation
One Rogers Street
Cambridge, MA 02142

Received on Tuesday, 8 January 2008 00:38:48 UTC