[Cbor] Tag 279 "Map entries for CBOR" in array format

worley@ariadne.com Thu, 18 February 2021 03:58 UTC

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Subject: [Cbor] Tag 279 "Map entries for CBOR" in array format
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A recent message pointed to:

> https://github.com/hildjj/cbor-map-entries 

I found it an odd read, as I couldn't figure out what the point is.  As
written, it's an alternative way to express maps, as a tag applied to an
array containing keys and values.  But what's the point?

The text starts off with "Although CBOR has support for generic Maps
(Major Type 5), some implementation languages (such as ECMAScript) have
two different types they might use to hold the information, depending on
whether all of the keys are strings or not."  And it makes sense that's
a problem to be solved.  But this document doesn't solve that, in that
neither tag-279-array nor CBOR map are constrained to have the keys be
strings, so both of them would have to be decoded into a more general
data type/structure.

Maybe I'm not read into CBOR enough to understand what is intended.  But
it seems to me that this document probably intended to specify that the
key values in a type-279-array must be strings.

Dale