aggregate-error-fences.ts:3:32 - error SC1090: extending AggregateError (its runtime layout carries a hidden errors slot a subclass would overlap — extend Error and keep the list in a field) is not supported yet

  2 | // Error layout, so subclasses fence like DOMException's.
  3 | class ValidationErrors extends AggregateError {
    |                                ^~~~~~~~~~~~~~
  4 |   constructor(errors: Error[]) {

aggregate-error-fences.ts:8:13 - error SC1090: constructing through a class value whose class has no lowering (the class declaration itself was rejected — see its own diagnostic) is not supported yet

  7 | }
  8 | console.log(new ValidationErrors([new Error("x")]).errors.length);
    |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  9 | 