import type { z, ZodArray } from 'zod';
/**
 * A merge rule attached to a Zod schema node via `withMergeRule`.
 * Controls how `mergeDataWithSchema` combines current and desired values at that node.
 *
 * - `replace`: Always replace current with desired (same as default leaf behavior)
 * - `by-key`: Merge array items by key — items in current not present in desired are kept
 */
export type MergeRule = {
    readonly kind: 'replace';
} | {
    readonly kind: 'by-key';
    readonly getKey: (item: unknown) => string;
};
/**
 * Retrieves the merge rule attached to a schema node, if any.
 */
export declare function getMergeRule(schema: z.ZodType): MergeRule | undefined;
/**
 * Creates a schema decorator that registers a merge rule on the schema node.
 *
 * ```typescript
 * z.object({ ... }).apply(withMergeRule({ kind: 'replace' }))
 * ```
 *
 * @param rule - The merge rule to attach
 * @returns A function that decorates a schema with the rule
 */
export declare function withMergeRule(rule: MergeRule): <T extends z.ZodType>(schema: T) => T;
/**
 * Creates a schema decorator that registers a `by-key` merge rule on an array schema.
 *
 * Infers the element type from the array schema so `getKey` is strongly typed.
 *
 * ```typescript
 * z
 *   .array(z.object({ ref: z.string(), value: z.number() }))
 *   .apply(withByKeyMergeRule({ getKey: (item) => item.ref }))
 * ```
 *
 * @param options - Options with a typed `getKey` function
 * @returns A schema decorator that annotates the array node with a by-key merge rule
 */
export declare function withByKeyMergeRule<T extends ZodArray>(options: {
    getKey: (item: z.output<T>[number]) => string;
}): (schema: T) => T;
//# sourceMappingURL=merge-rule-registry.d.ts.map