/**
 * The prefilter, client side.
 *
 * A deliberate reimplementation rather than a shared package: the server's copy is the reference,
 * and the point of keeping the language this dumb is that any client in any language can rewrite it
 * in twenty lines. A shared dependency would make that claim untestable and would couple every
 * platform's release cycle to the server's.
 *
 * It is a volume gate, not an expressiveness mechanism. **Nothing may depend on it.** A client that
 * ignores prefilters and reports every event is still correct, just louder — the server evaluates
 * the same condition again before spending anything.
 *
 * Every condition is ANDed. No OR, no regex, no arithmetic, no code.
 */
export type PrefilterScalar = string | number | boolean | null;
export type PrefilterCondition = PrefilterScalar | PrefilterScalar[] | {
    not: PrefilterScalar | PrefilterScalar[];
} | {
    exists: boolean;
};
/** Dot-path to condition. An empty or absent prefilter matches everything. */
export type Prefilter = Record<string, PrefilterCondition>;
export declare function matchesPrefilter(payload: unknown, prefilter?: Prefilter | null): boolean;
/** Reads `author.bot` out of `{ author: { bot: true } }`. Missing paths read as `undefined`. */
export declare function readPath(payload: unknown, path: string): unknown;