Update 07example.md to not have presence in the type definitions

[hassila]

I removed the presence field in the type definitions as they were removed for 2.0 to be field-only (which was a great change).

[hassila]

Hello? @kleihan or someone else?

[kleihan]

@hassila sorry for dropping the ball on this, We will review and merge. There has been very little activity on SBE v2.0 RC3 since quite a while.

[hassila]

Thanks @kleihan - saw your commits for ISO preparation and thought it worthwhile to ping.

[kleihan]

Thanks @kleihan - saw your commits for ISO preparation and thought it worthwhile to ping.

Note that the ISO submission will be SBE v1.0. Don has separated examples for proper validation into https://github.com/FIXTradingCommunity/fix-sbe-examples and these need to be reconciled into the spec.

[donmendelson]

The examples pass XML validation in XMLSpy. Presence attribute is indeed allowed on type that is a member of a composite. In the XSD, see XML type memberDataType, described as "A simple type used as a member of a composite type". It has attribute group presenceAttributes. The main use in composites is to set members as constant so they need not be transmitted on the wire.

[hassila]

@donmendelson thanks for clarification - I can see the issue for composites (although there’s some dissonance, as a systematic consistent approach would perhaps be to allow one to specify presence attributes for the subfields of the composite when declaring a composite field. Defining it on the type really just becomes a mechanism for defining constant as you say). Anyway, guess we can close this as such re-engineering is probably not worthwhile for what is a fringe case really. Thanks for your time.