/** The character sets `type` names, in the spelling the contract declares. */
export type PinInputType = 'text' | 'numeric' | 'alphanumeric' | 'alphabetic';
/** Builds the per-character predicate used to accept or reject each keystroke. */
export declare function pinCharAcceptor(type: PinInputType, pattern?: string): (char: string) => boolean;
/** Returns the pattern source {@link pinCharAcceptor} applies, defaulting to `'.'` for `'text'`. */
export declare function pinCharPattern(type: PinInputType, pattern?: string): string;
/**
 * The default accessible name for a pin box. `index` is 1-based (read aloud).
 *
 * @param index the box's position, counting from 1
 * @param length how many boxes the code has
 */
export declare function pinInputDigitLabel(index: number, length: number): string;