/** How a complete provider value is divided into streaming deltas. */
export type ChunkSpec = {
    /** Use the supplied delta sequence exactly. */
    readonly kind: "explicit";
    /** Deltas whose concatenation must equal the complete value. */
    readonly chunks: readonly string[];
} | {
    /** Split the UTF-16 string into fixed-size slices. */
    readonly kind: "fixed";
    /** Positive number of UTF-16 code units in each slice. */
    readonly size: number;
} | {
    /** Split the value by Unicode code point. */
    readonly kind: "characters";
};
/** Split a complete provider value according to a validated chunk specification. */
export declare function chunkString(value: string, spec: ChunkSpec): string[];