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positional predicates in canonical binding-expressions?

From: joern turner <joern@webman.de>
Date: Wed, 11 Jul 2001 04:57:12 -0400 (EDT)
To: www-forms@w3.org
Message-ID: <3B4B8234.1030709@webman.de>
in my effort to implement a web-based implementation i've come over some 
pratical problem with the current definition of canonical binding 
expressions in conjunction with repeat-elements.

i'm not an expert in xpath, but from my current understanding i need a 
'positional' predicate ( like e.g. [1] ) to completely handle 
(please correct me, if i've missed something!...)

although there's no problem while processing the form, it occurs when 
the collected instance-data have to be submitted via http as key/value 
pairs. as http makes no guarantee about the order of posted parameters, 
each single instance-value must be referenced uniquely by a canonical 
binding-expression, so the instance can be 're-assembled' on the server.

the repeat example clarifies the  problem:
(i hope this gets not too scrambled)


to submit these instance-data i see no other way than specifying a 
parameter with a positional predicate in the ref-attribute like this:


then the above data could be transferred in the following form (but 
arriving the server in no specific order)


the same problem applies for simple lists.

please excuse the lengthy mail and tell me about your thoughts in that area.
Received on Wednesday, 11 July 2001 05:03:49 UTC

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