ambiguity - mandatory alignment for text (12.1.2)
These two paragraphs contradict each other. When processing textual data, it is a schema definition error if the dfdl:alignment and dfdl:alignmentUnits properties are used to specify alignment that is not a multiple of the encoding-specified mandatory alignment. If the data is not aligned to the proper boundary for the encoding when textual data is processed, then bits are skipped (parsing) or filled from dfdl:fillByte (unparsing) to achieve the mandatory alignment. So is it to be SDE (conservative), or just move over to the mandatory alignment? E.g., <xs:sequence dfdl:encoding="utf-8" dfdl:alignment="7" dfdl:alignmentUnits="bits" dfdl:initiator="hello">.... The alignment property says 7 bits, but the initiator is utf-8 which requires 8 bits. So we either SDE, or we just add additional alignment bits to align the initiator text. Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com Please note: Contributions to the DFDL Workgroup's email discussions are subject to the OGF Intellectual Property Policy<http://www.ogf.org/About/abt_policies.php>
Agreed on WG call that there was no contradiction - the first is a rule about specifying alignment, the second is about skipping to an alignment. Regards Steve Hanson Architect, IBM Data Format Description Language (DFDL) Co-Chair, OGF DFDL Working Group IBM SWG, Hursley, UK smh@uk.ibm.com tel:+44-1962-815848 From: Mike Beckerle <mbeckerle.dfdl@gmail.com> To: "dfdl-wg@ogf.org" <dfdl-wg@ogf.org>, Date: 09/09/2013 15:59 Subject: [DFDL-WG] ambiguity - mandatory alignment for text (12.1.2) Sent by: dfdl-wg-bounces@ogf.org These two paragraphs contradict each other. When processing textual data, it is a schema definition error if the dfdl:alignment and dfdl:alignmentUnits properties are used to specify alignment that is not a multiple of the encoding-specified mandatory alignment. If the data is not aligned to the proper boundary for the encoding when textual data is processed, then bits are skipped (parsing) or filled from dfdl:fillByte (unparsing) to achieve the mandatory alignment. So is it to be SDE (conservative), or just move over to the mandatory alignment? E.g., <xs:sequence dfdl:encoding="utf-8" dfdl:alignment="7" dfdl:alignmentUnits="bits" dfdl:initiator="hello">.... The alignment property says 7 bits, but the initiator is utf-8 which requires 8 bits. So we either SDE, or we just add additional alignment bits to align the initiator text. Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com Please note: Contributions to the DFDL Workgroup's email discussions are subject to the OGF Intellectual Property Policy -- dfdl-wg mailing list dfdl-wg@ogf.org https://www.ogf.org/mailman/listinfo/dfdl-wg Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU
participants (2)
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Mike Beckerle -
Steve Hanson