/**
* `ElementInternals` attachment helpers, deliberately in their own module rather than in
* `form-associated.ts`.
*
* `form-associated.ts` calls `resolveLyraString(...)` for its validation messages, so the
* default-string slice generator treats ANY import from it as pulling that message key into the
* importing component's slice. `lr-toast` needs only `attachInternalsSafely()` and is not a form
* control, so importing it from there would ship a `fieldRequired` string in a toast region --
* exactly the incidental-key bloat 9.0.0 removed elsewhere. This module has no localization
* dependency at all, so importing it costs nothing.
*
* `form-associated.ts` re-exports both symbols, so existing importers are unaffected.
*/
/**
* Minimal ElementInternals substitute for DOM implementations that expose
* form-associated custom elements but do not implement `attachInternals()` yet.
* Keeping the shape here means components remain constructible in SSR/test DOMs;
* native browsers still use their real internals and form participation.
*
* Form participation (`setFormValue`, `form`, `labels`) is inert, since there is nothing to
* participate in, but `validity` and `states` are real: both are read back by components
* (`internals.validity.valid`, `internals.states.has(...)`), so a stub that always answers
* "empty" would report a *wrong* answer rather than a missing one. `states` can't drive CSS
* `:state()` matching without a real `ElementInternals` behind it — it degrades to an
* observable-but-unstyled record of the same state names a browser would expose.
*
* Exported for the form-associated controls that still manage `ElementInternals` directly instead
* of through this mixin -- `<lr-voice-picker>` and friends call `attachInternalsSafely()` below
* rather than hand-maintaining a second copy of this shape. ("Their value isn't a plain string" was
* the reason for years and no longer is: the mixin takes a `FormValueAdapter` and carries any value
* type. Those controls are a migration backlog, frozen shrink-only by rule (f) of
* `scripts/check-form-associated.mjs`, not a second supported pattern.)
*/
export declare function createFallbackInternals():ElementInternals;
/**
* `host.attachInternals()`, degrading to `createFallbackInternals()` rather than throwing when the
* host environment either has no such method at all (a DOM shim that stops short of
* `ElementInternals`) or has one that throws (already-attached internals, a partial polyfill).
* Direct property access is deliberately avoided: a partial DOM can expose `attachInternals`
* through an accessor that throws before a callable can be saved. Only an own or inherited data
* descriptor is eligible, and the saved callable is invoked exactly once. Constructing a control
* must never be the thing that breaks a downstream consumer's non-browser test suite.
*/
export declare function attachInternalsSafely(host:HTMLElement):ElementInternals;