/**
 * This is the basic schema type.
 * All schema types should inherit from this class.
 * For example:
 *
 * ``` js
 * class SchemaTypeCustom extends SchemaType {};
 * ```
 *
 * **Query operators**
 *
 * To add a query operator, defines a method whose name is started with `q$`.
 * For example:
 *
 * ``` js
 * SchemaTypeCustom.q$foo = function(value, query, data){
 *   // ...
 * };
 * ```
 *
 * The `value` parameter is the value of specified field; the `query` parameter
 * is the value passed to the query operator; the `data` parameter is the
 * complete data.
 *
 * The return value must be a boolean indicating whether the data passed.
 *
 * **Update operators**
 *
 * To add a update operator, defines a method whose name is started with `u$`.
 * For example:
 *
 * ``` js
 * SchemaTypeCustom.u$foo = function(value, update, data){
 *   // ...
 * };
 * ```
 *
 * The `value` parameter is the value of specified field; the `update` parameter
 * is the value passed to the update operator; the `data` parameter is the
 * complete data.
 *
 * The return value will replace the original data.
 */
declare class SchemaType<T> {
    name: string;
    options: {
        required: boolean;
        default?: (() => T) | T;
    };
    default: () => T;
    /**
     * SchemaType constructor.
     *
     * @param {String} name
     * @param {Object} [options]
     *   @param {Boolean} [options.required=false]
     *   @param {*} [options.default]
     */
    constructor(name?: string, options?: {
        required?: boolean;
        default?: (() => T) | T;
    });
    /**
     * Casts data. This function is used by getters to cast an object to document
     * instances. If the value is null, the default value will be returned.
     *
     * @param {*} value
     * @param {Object} data
     * @return {*}
     */
    cast(value?: unknown, data?: unknown): unknown;
    /**
     * Validates data. This function is used by setters.
     *
     * @param {*} value
     * @param {Object} data
     * @return {*|Error}
     */
    validate(value: unknown, data?: unknown): unknown;
    /**
     * Compares data. This function is used when sorting.
     *
     * @param {*} a
     * @param {*} b
     * @return {Number}
     */
    compare(a: unknown, b: unknown): number;
    /**
     * Parses data. This function is used when restoring data from database files.
     *
     * @param {*} value
     * @param {Object} data
     * @return {*}
     */
    parse(value: unknown): any;
    /**
     * Transforms value. This function is used when saving data to database files.
     *
     * @param {*} value
     * @param {Object} data
     * @return {*}
     */
    value(value: unknown, data?: unknown): any;
    /**
     * Checks the equality of data.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    match(value: T, query: unknown, data?: unknown): boolean;
    /**
     * Checks the existance of data.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$exist(value: unknown, query: unknown, data?: unknown): boolean;
    /**
     * Checks the equality of data. Returns true if the value doesn't match.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {boolean}
     */
    q$ne(value: T, query: unknown, data?: unknown): boolean;
    /**
     * Checks whether `value` is less than (i.e. <) the `query`.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$lt(value: unknown, query: unknown, data?: unknown): boolean;
    /**
     * Checks whether `value` is less than or equal to (i.e. <=) the `query`.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$lte(value: unknown, query: unknown, data?: unknown): boolean;
    /**
     * Checks whether `value` is greater than (i.e. >) the `query`.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$gt(value: unknown, query: unknown, data?: unknown): boolean;
    /**
     * Checks whether `value` is greater than or equal to (i.e. >=) the `query`.
     *
     * @param {*} value
     * @param {*} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$gte(value: unknown, query: unknown, data?: unknown): boolean;
    /**
     * Checks whether `value` is equal to one of elements in `query`.
     *
     * @param {*} value
     * @param {Array} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$in(value: unknown, query: unknown[], data?: unknown): boolean;
    /**
     * Checks whether `value` is not equal to any elements in `query`.
     *
     * @param {*} value
     * @param {Array} query
     * @param {Object} data
     * @return {Boolean}
     */
    q$nin(value: unknown, query: unknown[], data?: unknown): boolean;
    /**
     * Sets the value.
     *
     * @param {*} value
     * @param {*} update
     * @param {Object} data
     * @return {*}
     */
    u$set<T>(value: unknown, update: T, data?: unknown): T;
    /**
     * Unsets the value.
     *
     * @param {*} value
     * @param {*} update
     * @param {Object} data
     * @return {*}
     */
    u$unset<T>(value: T, update: boolean, data?: unknown): T | undefined;
    /**
     * Renames a field.
     *
     * @param {*} value
     * @param {*} update
     * @param {Object} data
     * @return {*}
     */
    u$rename(value: unknown, update: string, data: unknown): void;
    q$exists: SchemaType<T>['q$exist'];
    q$max: SchemaType<T>['q$lte'];
    q$min: SchemaType<T>['q$gte'];
}
export default SchemaType;