Open
Description
Describe the proposed feature
CDDL is the notational convention for describing CBOR data structures (https://datatracker.ietf.org/doc/html/rfc8610) - think JSON Schema for CBOR - though it is also useful for JSON as well.
What other libraries (C++ or other) have this feature?
None :(. This page (cbor-wg/cddl#29) tracks implementations and there seem to be none in C/C++. So you could be the first!