NFD » NDN Specifications

This is a low priority issue in case we officially allow flexible type codes for a NameComponent. (Right now we have Generic and ImplicitSha256DigestComponent.) If an application uses a name component with code 19, it won't be able to put it in an Exclude because this is the same type code as Any.
https://github.com/named-data/NDN-TLV/blob/master/interest.rst#exclude

In this possible future scenario, it might be necessary to prohibit type code 19, or say that an application won't be able to exclude it, or modify the definition of Exclude so that the NameComponent is wrapped inside another TLV, as we do for MetaInfo FinalBlockId.
https://github.com/named-data/NDN-TLV/blob/master/data.rst#finalblockid

Anyway, if we definitively decide never to support flexible name component types, we can abandon this issue.