import type { SchemaOptions } from "./Schema.js";
import { Schema } from "./Schema.js";
/** Function that sanitizes a string. */
export type Sanitizer = (str: string) => string;
/** Options for `StringSchema` */
export interface StringSchemaOptions extends SchemaOptions {
    readonly value?: string | undefined;
    readonly min?: number | undefined;
    readonly max?: number | undefined;
}
/**
 * Schema that defines a valid string.
 *
 * @example
 *  const schema = new StringSchema({ default: 'abc', required: true, min: 2, max: 6, match: /^[a-z0-9]+$/, trim: true });
 *  schema.validate('def'); // Returns 'def'
 *  schema.validate('abcdefghijk'); // Returns 'abcdef' (due to max)
 *  schema.validate(undefined); // Returns 'abc' (due to value)
 *  schema.validate('   ghi   '); // Returns 'ghi' (due to schema.trim, defaults to true)
 *  schema.validate(1234); // Returns '1234' (numbers are converted to strings)
 *  schema.validate('---'); // Throws 'Incorrect)
 *  schema.validate(true); // Throws 'Must be)
 *  schema.validate(''); // Throws Required
 *  schema.validate('j'); // Throws 'Minimum 3 chaacters'
 */
export declare class StringSchema extends Schema<string> {
    readonly value: string;
    readonly min: number;
    readonly max: number;
    constructor({ min, max, value, ...options }: StringSchemaOptions);
    validate(unsafeValue?: unknown): string;
    /** Sanitize the string by removing unwanted characters. */
    sanitize(str: string): string;
}
/** Valid string, e.g. `Hello there!` */
export declare const STRING: StringSchema;
/** Valid string, `Hello there!`, with more than one character. */
export declare const REQUIRED_STRING: StringSchema;