[Cbor] Validity checking and tags

Laurence Lundblade <lgl@island-resort.com> Sun, 03 November 2019 16:57 UTC

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Subject: [Cbor] Validity checking and tags
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Some CBOR protocols will require use of a tag to indicate a particular data type (on a per instance basis) and others will explicitly prohibit use of a tag (on a per instance basis).

That implies that generic validity processing can only be performed on data items that are explicitly tagged. For example generic processing can’t check the internal structure of a decimal fraction for validity unless it is tagged. It just won’t know that it is a decimal fraction.

I think we expect protocols using using these new / custom / registered / bespoke data types to not require instances to be tagged, so validity checking will be limited. 

I think this is mostly OK, but wanted to point it out.

(We refer to these new / custom / registered / bespoke data types primarily as tagged, but then say the tag is not necessary; I think this is confusing). 

LL