import type { MotionPreference } from '../contracts/motion.js';
export declare const reactViewTransition: unknown;
type UpdateFn = () => void | Promise<void>;
/** --ag-duration-micro as the cascade resolves it on `el` (REQ-MAT-48: micro is
    read from the computed CSS, so a theme or mode that rebinds it is honoured).
    The generated token value applies only when no token sheet is loaded. */
export declare function computedMicroMs(el: Element | null | undefined): number;
/** startMorph(update, { surfaces, name }): §4.7 imperative path. */
export declare function startMorph(update: UpdateFn, opts?: {
    surfaces?: Element[];
    name?: string;
    motion?: MotionPreference;
}): Promise<void>;
/** Sanitised unique morph name: `ag-<prefix>-<useId>` reduced to [a-z0-9-].
    Duplicate registration happens in an effect (StrictMode-safe); a dev-only
    console warning fires when two live surfaces share a name. */
export declare function useMorphName(prefix: string): string;
export {};
//# sourceMappingURL=viewTransition.d.ts.map