- Privates ride the ordinary member maps under their unspellable spelled names; a subclass redeclaring an inherited private name is fenced, so base-chain walks ARE lexical resolution and privates never enter vtables — JS's no-dynamic-dispatch semantics by construction.
- Private GENERATOR methods compose the generator machinery with this as param 0 through the gen-spawn wrapper (the vtable problem that keeps public generator methods fenced does not exist for privates); async and generic privates ride their existing static-dispatch machinery.
- Private statics lower as module globals/functions through the declaring class's own name; subclass-named and class-value receivers fence (JS brands the declaring constructor alone).
- '#x in obj' lowers as instanceof-the-declarer: static folds at/below and disjoint, the vtable interval test when the declarer sits below the receiver's static class, and unions of decided class arms collapse to tag tests; unknown/generic/static brands fence with pointed hints.
- util.inspect omits private fields exactly like Node (an all-private class prints 'C {}'); corpus 2450-2457 pin every form differentially on both backends, diagnostics private-members pins the fences.
Chris Tate