Re: [Cbor] CDDL style questions

[Brian E Carpenter <[e-mail]>]

Mainly I agree with Carsten, perhaps because I developed the CDDL for GRASP under his tuition. So I have snipped everything except one point.
On 2018-11-23 04:03, Carsten Bormann wrote:
...
> Without knowing all the details of C-DNS, I would expect that 
> 
>>    Port = uint .size 2
> 
> is a good type to have at hand and use where the semantics ask for a TCP/UDP port.
> 
> (It also immediately exposes the question whether it shouldn’t really be
> 
>     Port = 1..0xFFFF
> 
> i.e., whether 0 should be excluded here. Of course, I don’t know what the answer to that question would be for C-DNS.)

For GRASP we ended up with:

port-number = 0..65535

one reason being that you can indicate an undefined port number by using 0. So it rather depends whether you are defining the type to use in a signaling message (as for GRASP) or to use in an actual transport header.

If anyone cares, the full GRASP CDDL is at https://tools.ietf.org/html/draft-ietf-anima-grasp-15#section-5 .

I did have one regret - using hyphens in names. When writing Python code using the same names, I had to change them all to underscore. Not serious, but a bit annoying.

I felt bad about including:

IPPROTO_TCP = 6
IPPROTO_UDP = 17

I wished I could have imported those from somewhere. As an extension to the style question, is there a role for a library of include files?

    Brian