[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: stupid URI tricks was: Re: URIs harmful


math tricks
> > No. Every URI _always_ identifies a resource.
>
>Only if you allow that some things with URI syntax aren't really
>URIs. For example, "http://www.cs.usyrtis.mars/rfc/rfc32767.txt"
>doesn't represent any resource at present:  there is no
>University of Syrtis to serve as the authority, and the RFC
>sequence has only reached the 3000s.
>
>oh right. I suppose the URI has to be 'legal' or 'valid' or
>needs some other such descriptor attached to it.

Arg!  I really really really have issues about this (ok, not personal issues 
:-).

The mere fact that it is possible to create URIs for resources which don't 
exist at the time of their creation implies that 'invalid' identifiers are 
just as much URIs as 'valid' ones.  Take math as a example:

Here's a function, y = 3x + 1

I could come up with a URI for mathematical variables such as 
'urn:math:_variable_Name_'.  So the identifier for 'y' could be 
'urn:math:y', which maps to '3x+1'.  The variable 'x' can also be identified 
by a uri, 'urn:math:x'.  However, 'x' hasn't been defined yet, so:

uri -> representation
urn:math:y -> 3 * urn:math:x + 1
urn:math:x -> undefined

Thus, 'invalid' URIs are useful as well as 'valid' ones when defining a 
behavior or function.

Another case for 'invalid' URIs are base URIs.  For a document, the base may 
be: 'http://www.pitt.edu/~jfcst24/'  That URI doesn't point to anything; 
there is no representation for it nor is it dereferenceable.  Thus, the URI 
is not valid.  However, the relative URI 'LexX/lexx.html', from the previous 
base URI, is dereferenceable and thus valid.  This is a another case where 
invalid URIs are useful as a base for other relative URIs (so they can be 
valid and dereferenced).


---
Jimmy Cerra
"If the path is set in stone, use a sledgehammer"


_________________________________________________________________
Join the worldÂ’s largest e-mail service with MSN Hotmail. 
http://www.hotmail.com


PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
 

Stylus Studio has published XML-DEV in RSS and ATOM formats, enabling users to easily subcribe to the list from their preferred news reader application.


Stylus Studio Sponsored Links are added links designed to provide related and additional information to the visitors of this website. they were not included by the author in the initial post. To view the content without the Sponsor Links please click here.

Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery ™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2013 All Rights Reserved.