RE: [xri] The case for being insensitive

From
Wachob, Gabe <>
Date
2003-09-17T21:41:22+00:00
ID
Thread
RE: [xri] The case for being insensitive
Title: Message

+1

 

I 
think Loren's understanding is reasonable and should be the approach of the TC. 

 

Comments are removed for the purposes of equivalence & 
normalization (this is my understanding - which I do not know we have 
discussed) so the case sensitivity issue is not impacted here because case 
sensitivity is a normalization/equivalence rule. The wording needs to be 
explicit. This assumes we agree on the "comment" mechanism, which we have not 
yet agreed to.

 

Little 
Quibbles:

We 
have to be careful with the wording "manager of each namespace" - a concept I'm 
not sure we've discussed before. This is a quibble - we can reword this in the 
terminology and conceptual framework of the current spec.  Also the "byte 
for byte" equivalence statement should probably be "character for character 
after NFC normalization" (which I believe it is now). 

 

    -Gabe

  
-----Original Message-----
From: Loren West 
  [mailto:]
Sent: Wednesday, September 17, 2003 
  1:46 PM
To: 'Lindelsee, Mike'; 
  
Subject: [xri] The case for being 
  insensitive

  
Hi 
  TC'ers,

  
 

  
I 
  agree with Mike except for the comment portion of the XRI.  Maybe the 
  spec. should read:

  
 

  
Two 
  XRIs are equivalent if the NON-COMMENT portions of the XRIs are byte-for-byte 
  equivalent.

  
 

  
That being the normative part of the spec.  At this point, some 
  people may mis-interpret the intent (as I did), so maybe a discussion of case 
  sensitivity in regards to resolution should follow 
  (non-normative):

  
 

  
During resolution, the manager of each namespace may have their own 
  rules for case sensitivity and equivalence in general.  
  One namespace owner might consider "Invoice" and "invoice" to be the same 
  for the purposes of resolution.  Another may consider "grey" and "gray" 
  to be the same.  Since you can't know that without invoking the 
  resolution process, they should be considered different XRIs that happen 
  to point to the same resource.

  
 

  
Obviously, this is a sensitive issue  :-)

  
 

  
=Loren 

  
    

    
-----Original Message-----
From: Lindelsee, 
    Mike [mailto:] 
Sent: Wednesday, September 17, 
    2003 11:57 AM
To: 
Subject: RE: 
    [xri] Draft -07 feedback from another Visa person (responses 
    cont'd)

    
Hi 
    All,

    
 

    
I'd like to follow up on the case-insensitivity 
    issue and mention what I see as a reasonable example that would argue 
    against case-insensitivity.  In my experience, the vast majority of my 
    accounts/login IDs on various systems are case sensitive.  Also, in 
    unix-based systems (and many others), most identifiers (anything in the 
    file system for sure) are case sensitive.  If any of 
    these identifiers are to be used in XRIs, the case-sensitivity 
    would need to be maintained, or ambiguity would be 
    introduced.

    
 

    
Between this issue and the Unicode issue, it seems 
    to me that it would be a bad idea to try to make any part of an XRI case 
    insensitive.

    
 

    
Mike

    
      
-----Original Message-----
From: Loren West 
      [mailto:]
Sent: Thursday, September 04, 
      2003 11:36 AM
To: 'Dave McAlpin'; 'Sakimura, Nat'; 'Wachob, 
      Gabe'; 
Subject: RE: [xri] Draft -07 
      feedback from another Visa person (responses cont'd)

      
Case insensitivity is a form of normalization that a large 
      population of people receive benefit from.  If there's a way to 
      provide that benefit to those people without degrading functionality where 
      it doesn't make sense, then I think we should do it.

      
 

      
I'd hate to see case insensitivity for ALPHA characters go 
      away.

      
 

      
=LOREN

      
 

      

      
-----Original Message-----
From: 
      Dave McAlpin [mailto:] 
Sent: Thursday, 
      September 04, 2003 11:06 AM
To: 'Sakimura, Nat'; 'Wachob, Gabe'; 
      
Subject: RE: [xri] Draft -07 feedback 
      from another Visa person (responses cont'd)

      
        

        
So are we OK 
        with case-insensitive comparison for ALPHA characters in the authority 
        component, or should we drop this altogether?

        
 

        
-----Original 
        Message-----
From: 
        Sakimura, Nat [mailto:] 
Sent: Thursday, September 04, 2003 
        10:57 AM
To: Dave 
        McAlpin; Wachob, Gabe; 
Subject: RE: [xri] Draft -07 
        feedback from another Visa person (responses cont'd)

        
 

        
I do not think 
        that there is a good way of introducing “case insensitivity” to Unicode 
        in general. 

        
Case 
        insensitivity is a form of normalization, which is very problematic for 
        the international character set. IMHO, only meaningful form of general 
        equivalence is the bit to bit comparison or the comparison of the 
        resolved result from the same authority. 

        
 

        
Nat

        
 

        

        
-----Original 
        Message-----
From: Dave 
        McAlpin [mailto:] 
Sent: Friday, September 05, 2003 
        2:43 AM
To: 'Wachob, 
        Gabe'; 
Subject: RE: [xri] Draft -07 
        feedback from another Visa person (responses cont'd)