Codex round-2 review found three adjacent fail-open shapes:
- Wrapped function expressions escaped classification: parentheses,
as/satisfies casts, and non-null assertions are now peeled before the
arrow/function test (initializers and default exports), and a
single-call-signature type literal counts as the surface signature.
A literal mixing call/construct signatures with anything else is
refused outright — no single signature to hold the tags against.
- The blanket 'export import X = N.member' skip was unsound (the target
can be a non-exported namespace member no walk visits): an alias now
documents itself.
- The heritage extra-parameter duty missed binding-pattern extras,
which no base declaration can name: they now trigger the standard
binding-pattern violation.
Five new negative-path tests pin the closed shapes; module doc and RFC
updated.
eaac3b58a4