export declare class GPT4Tokenizer {
    private vocab;
    private nMergedSpaces;
    private nVocab;
    private encodings;
    private decodings;
    private byteEncoder;
    private byteDecoder;
    private bpeRanks;
    private cache;
    private encodeCache;
    private textEncoder;
    private textDecoder;
    constructor(options: {
        type: 'gpt3' | 'gpt4' | 'codex';
    });
    private initialize;
    private zip;
    private bytesToUnicode;
    getPairs(word: string[]): Set<[string, string]>;
    bpe(token: string): string;
    encode(text: string): number[];
    encodeUtf8(text: string): Uint8Array;
    decodeUtf8(bytes: Uint8Array): string;
    decode(tokens: number[]): string;
    estimateTokenCount(input: string): number;
    chunkText(text: string, maxTokensPerChunk: number): {
        text: string;
        bpe: number[];
    }[];
    private decodeTokensToBytes;
    private getUtf8SafeTokenBoundaries;
}
export default GPT4Tokenizer;