/**
 * Utility predicates for number mask processing.
 */
/** Returns true if the string contains one or more zeros and nothing else. */
export declare const isAllZeros: (str: string) => boolean;
/** Returns true if the string is empty or contains only zeros. */
export declare const isEmptyOrAllZeros: (str: string) => boolean;
/** Returns true if the string is a single non-zero digit (1-9). */
export declare const isNonZeroDigit: (str: string) => boolean;
