/**
* CSS custom states (`:state()`), and the six validity states every form-associated control in the
* library publishes.
*
* These functions exist standalone because only 11 of the library's 28 form-associated controls use
* the `FormAssociated` mixin — the rest drive `ElementInternals` directly, because their value is
* not a string. The validity states were therefore reachable on some controls and silently absent
* on others, which is worse than absent everywhere: a consumer writes
* `lr-thing:state(user-invalid) { … }`, sees it work on `lr-input`, and ships a stylesheet that
* quietly does nothing on `lr-checkbox`.
*/
/**
* Adds or removes one CSS custom state, tolerating every environment that cannot take it: a DOM
* with no `ElementInternals` at all (`states` undefined behind a shim), and the engines that
* shipped `CustomStateSet` accepting only dashed idents. A custom state is a styling convenience,
* so a rejected state name must never break the validity it describes.
*/
export declare function setCustomState(internals:ElementInternals|undefined,name:string,present:boolean):void;
/**
* Publishes the six validity custom states — `required`/`optional`, `valid`/`invalid`,
* `user-valid`/`user-invalid` — so a consumer can style a control's validation state with
* `lr-thing:state(user-invalid) { … }` without reaching into its shadow root.
*
* `valid` mirrors `validity.valid`. The `user-*` pair additionally requires that the user has
* INTERACTED (an `input`/`change`/blur on this control, or a `reportValidity()` call, which is what
* a submit attempt runs) — that is the whole point of the pair: a pristine required field is
* invalid, but styling it red before the user has typed anything is hostile.
*
* `barred` (see `isBarredFromValidation()` in `internal/form-associated.ts`) silences BOTH pairs:
* a control barred from constraint validation — disabled, fieldset-disabled, readonly — matches
* neither `:valid` nor `:invalid` natively, and publishing `invalid`/`user-invalid` from one is
* what made the documented `lr-input:state(user-invalid) { border-color: red }` rule paint every
* disabled required field red. `required`/`optional` describe the attribute rather than the
* validation outcome, so they keep publishing exactly like native `:required`/`:optional`.
*/
export declare function syncValidityStates(internals:ElementInternals|undefined,options:{required:boolean;hasInteracted:boolean;barred?:boolean;}):void;