import type { Logger } from './types.js';
/** @internal */
export declare const NOOP_LOGGER: Logger;
/** @internal */
export declare function assertString(value: unknown, name: string): asserts value is string;
/** @internal */
export declare function assertBytes(value: unknown, name: string): asserts value is Uint8Array;
/** @internal */
export declare function assertCompressedPubkey(value: unknown, name: string): asserts value is Uint8Array;
/**
 * The message of the deepest meaningful error in a cause chain.
 *
 * Walks `err.cause` links (capped at 16 hops, cycle-safe) and returns the
 * message of the deepest link that has one. Rules, in order, at each link:
 *
 * - A string link is its own message.
 * - An object link with a non-empty string `message` contributes that message.
 * - An object link with an empty message but an `errors` array (an
 *   `AggregateError`, e.g. a Node fetch failure against a host with several
 *   addresses) contributes the first sub-error's message.
 * - A link with no usable message is skipped, so the nearest non-empty
 *   message above it in the chain wins.
 *
 * Never throws: throwing getters, null-prototype objects, and non-Error
 * values all degrade to `String(value)` or `'Unknown error'`.
 *
 * @param err The caught value whose root cause message to extract.
 * @returns A non-empty, human-readable message.
 */
export declare function rootCauseMessage(err: unknown): string;
/**
 * The DID Resolution error code of a caught value.
 *
 * Walks `err.cause` links from the top (capped at 16 hops, cycle-safe) and
 * returns the `type` of the first link that is a {@link DidMethodError} whose
 * type is a member of {@link MethodErrorCode}. The nearest typed link wins, so
 * a wrapper that re-types a deeper failure decides the code. Every other value
 * maps to `INTERNAL_ERROR`, the code DID Resolution v1 gives to an unexpected
 * error. Never throws.
 *
 * @param err The caught value.
 * @returns A member of {@link MethodErrorCode}.
 */
export declare function resolutionErrorCode(err: unknown): string;
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