import { BlockhashWithExpiryBlockHeight, Commitment, Connection } from '@solana/web3.js';
import { BlockhashFetcher } from './types';
export declare class BaseBlockhashFetcher implements BlockhashFetcher {
    private connection;
    private blockhashCommitment;
    constructor(connection: Connection, blockhashCommitment: Commitment);
    getLatestBlockhash(): Promise<BlockhashWithExpiryBlockHeight | undefined>;
}