List of Missing Semantic Checks

[wenovus]

Today, the yang package's role is to generate an user-friendly IR in Go (i.e. the Entry tree) that downstream libraries can use, leaving the job of doing the complete set of semantic checks to more complete checkers like pyang.

In order to be a complete compiler front-end, a complete set of semantic checks would be needed, wherein the output Entry tree can be assumed to be completely valid, without any YANG errors.

The list tracks the missing checks (as they're found), so that we know where to start if we ever need this feature from goyang.

• Extensions usages should have a corresponding declaration.
• duplicate prefixes are not allowed.
• The "default" statement MUST NOT be present on choices where "mandatory" is "true".