Re: [Cbor] Ordering of items in the prefix table

Michael Richardson <mcr+ietf@sandelman.ca> Sat, 05 September 2020 03:10 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
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Date: Fri, 04 Sep 2020 23:10:15 -0400
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Subject: Re: [Cbor] Ordering of items in the prefix table
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Brendan Moran <Brendan.Moran@arm.com> wrote:
    > I’ve been thinking about how dictionaries and nested tables interact. I
    > have been wondering about the possibility of using references that
    > overflow the nearest table to handle nesting. For the nesting-only
    > case, this is straight-forward: when the decoder encounters a
    > reference, it first checks to see if the reference fits in the nearest
    > table. If it overflows the number of elements in that table, the size
    > of the table is subtracted from the reference, then the decoder checks
    > the next-nearest table.

That's a good idea, and it allows the shorter references to be reused.
It also allows for locality, so we no longer have to worry about the global
frequency, but some local frequency of use.

--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide