- From: Alessandro Vernet <avernet@orbeon.com>
- Date: Wed, 4 Jan 2006 19:04:06 -0800
- To: public-xml-processing-model-wg@w3.org
Notes: 1. Some requirements below are taken from "XML Processing Model Requirements" (5 April 2004) [1]. Our intention is to emphasis the importance of some requirements mentioned in [1] by including them here. Requirements 1 to 5 below fall in this category and some of the wording has been modified. 2. The list below is numbered to make it easier to reference a particular requirement. The position in the list does not reflect the importance of a given requirement. 3. The make the discussion easier in this working group, we should agree on a common vocabulary and come up with a set of definitions sooner than later. For the sake of this list, we will use the following vocabulary. The "language" refers to the XML Processing Language. A specific file in the language is referred to as a "process". The language allows the use of "XML processors" like XSLT, W3C schema validation, SOAP call. A specific call to an XML processor in a process is an "operation". Requirements for the XML Processing Language: 1. It should be relatively easy to implement a conformant implementation of the language, but it should also be possible to build a sophisticated implementation that can perform parallel operations, lazy or greedy processing, and other optimizations. 2. The language should not prohibit an implementation from streaming operations, for instance starting processing a second operation that depends on the output of a first operation before the output of the first operation is entirely completed. 3. The language should allow conditional processing so that different operations are selected depending on run-time evaluation. This could be not unlike conditional processing in XSLT [2]. 4. The language should allow XML processors to accept zero, one or multiple inputs and zero, one or multiple outputs. 5. The language should be expressed in XML. It should be possible to author and manipulate documents expressed in the pipeline language using standard XML tools. 6. Just like an XML processor, a process should be able to accept zero, one or multiple inputs and zero, one or multiple outputs. 7. The language should provide mechanisms for repetition a number of operations. The two most common forms of repetition found in languages are "for-each" and "while". The language should allow for "for-each" repetitions where a number of operations are executed on a set of documents. This could be not unlike repetition in XSLT [3]. The language could allow for "while" repetition where a number of operations are executed while a condition is met. 8. The language could provide mechanisms for addressing error handling and fallback behaviors. [1] http://www.w3.org/TR/2004/NOTE-proc-model-req-20040405/ [2] http://www.w3.org/TR/2005/CR-xslt20-20051103/#conditionals [3] http://www.w3.org/TR/2005/CR-xslt20-20051103/#for-each Alex -- Blog (XML, Web apps, Open Source): http://www.orbeon.com/blog/
Received on Thursday, 5 January 2006 03:04:15 UTC