33.9. External correspondence — the metadata family🔗

@[requirement], @[dybkaer] and @[vim4] record what an external document says about a declaration. All three are advisory, and all three already have their own generated index: the requirement-traceability matrix in the Requirements section maps every numbered requirement to the declarations that specify, prove, implement or exemplify it, and the two correspondence tables in the External Cross-References chapter map Dybkær sections and VIM clauses to this work's declarations. They are listed in the reference table above for completeness and are not duplicated here.