- From: James Fuller <james.fuller.2007@gmail.com>
- Date: Mon, 8 Dec 2008 15:29:39 +0100
- To: "David A. Lee" <dlee@calldei.com>
- Cc: public-xml-processing-model-comments@w3.org
On Mon, Dec 8, 2008 at 3:21 PM, David A. Lee <dlee@calldei.com> wrote: > Am I misreading things ? > I dont think its "legal" to change the default binding in an implementation > specific way, > if its in violation of the specs. The specs clearly say the binding is the > "default readable port". > I'm going to "do" it but it wont be "legal". > fair enough, but you are able to add extension attributes e.g. 3.8 Extension attributes ... which you can then use to subvert all manner of XProc behavior (which is illegal!). > When I get further along in the implementation I will indeed take you up on > that idea of sending more test cases. good stuff. > However in this case, I cant even imagine a useful case where this case > would be used, Which is one reason I'm objecting. > Plus if my implementation can "pass" the tests while I know myself its > "broken" because I am not going to implement this part, > why should I submit a test case to "break" it :) yes, you are right, but it would be nice to have any test cases that characterize weaknesses in streaming. in any event, I would at least add an extension attribute to turn on / off the default illegal behavior. gl, Jim Fuller > -David > > >> Hello David, >> >> Perhaps at this very late stage something could be added to define the >> default binding, in fact you can do this yourself as an extension to >> xproc quite legally. >> >> Streaming is a form of optimization and I think that XProc did >> potentially too much 'early optimization' type thinking throughout >> discussions on the spec. Lets be confident that we will discover the >> ways later on to inform a v2 ... e.g. if people use it, it will no >> doubt find its way into later/future versions. >> >> btw, as an implementator you will benefit from existing test cases and >> I would say why not submit representative missing test case u mention. >> >> cheers, Jim Fuller >> >> >> >> >> >> On Mon, Dec 8, 2008 at 2:39 PM, David A. Lee <dlee@calldei.com> wrote: >>> >>> I would like to formally object to the following sections of the XProc: >>> An >>> XML Pipeline Language specification, >>> W3C Candidate Recommendation 26 November 2008 >>> >>> Sec 5.7.3 p:with-option >>> Sec 5.7.4 p:with-param >>> >>> The objection is to the default binding of the context for the select= >>> attributes, >>> which in these sections are defined to be the default readable port. >>> I propose that the default binding should be <p:empty/> unless explicitly >>> bound. >>> >>> A summary of my objection is that in my opinion, as a implementer of the >>> xproc standard, >>> that this prevents a conforming xproc implementation from potentially >>> streaming through >>> any action that uses any parameters or options specified with >>> p:with-option >>> and p:with-param >>> because the processor would have to collect (fork and buffer) the input >>> for >>> use by the select >>> attribute prior to starting the action, even if the xpath expression did >>> not >>> reference any context. >>> In my opinion, the advantage to the user for this convenience is far >>> outweighed by the cost >>> to the implementation. In fact the current test suites do not have a >>> single >>> case where the context >>> is actually used. By coding this into the specs it is placing an >>> extreme >>> burden onto future implementations >>> and onto the potential performance of any future implementations, with , >>> in >>> my opinion, little or no value to >>> xproc pipeline authors. >>> >>> In my implementation of xproc I intend on not implementing this portion >>> of >>> the spec due to these concerns. >>> >>> Note there was an alternative suggested for implementers, which is >>> performing full static analysis of the xpath option >>> to determine if a context is referenced. I suggest this is an undue >>> amount of effort required for implementers of this >>> specification, considering a goal of the spec is to allow implementations >>> to >>> reuse existing standard libraries which do >>> not have this capability. A simple change to the spec would eliminate >>> this >>> burden while not having a significant >>> impact on usefulness to pipeline authors. >>> >>> >>> Please refer to threaded discussions in the XProc mailing list >>> >>> http://lists.w3.org/Archives/Public/xproc-dev/2008Nov/0055.html >>> http://lists.w3.org/Archives/Public/xproc-dev/2008Dec/0011.html >>> >>> >>> Thank You. >>> ----------------------------------------------------------- >>> David A. Lee, >>> President DEI Services Inc. >>> dlee@calldei.com >>> http://www.calldei.com >>> http://www.xmlsh.org >>> >>> ---------------------------------------- >>> David A. Lee >>> Senior member of the technical staff >>> Epocrates, Inc. >>> dlee@epocrates.com >>> >>> ------------------------------------------------ >>> David A. Lee >>> CTO >>> Nexstra, Inc. >>> dlee@nexstra.com >>> www.nexstra.com >>> >>> >> > >
Received on Monday, 8 December 2008 14:30:15 UTC