SP009 DuplicateDeclaredParentError

DeprecatedError — Sometimes, code will change, and the conditions under which that error was required are no longer valid, so the error is deprecated.

This error is retired and its code will not be reused. It used to mean a declaration named more than one parent with an in clause. The clause has been removed, so there is no longer any way to name a parent at all, let alone twice.

Decided in

• ADR012 FileScopeUniverse (isDeprecatedBy) — Accepted

In the compiler

• packages/prose-parser/src/errors.js:211