import { AsyncMapper, Mapper } from 'augmentative-iterable';
export interface JoinFunction<T> {
    /**
     * Projects and concatenates the elements of the iterable into a `string` using a separator. This is a resolving operation, will cause a full loop through all the elements of the iterable.<br>
     *   Examples:<br>
     *     * `fluent(['anchor', 'almond', 'bound', 'alpine']).join(', ')` returns *anchor, almond, bound, alpine*
     * @param separator The separator to use in between the elements of the iterable.
     * @param mapper The function which projects the elements of the iterable into `string`s. Falls back to the identity function if omitted.
     * @returns The concatenated string of the elements in the iterable.
     */
    (separator: string, mapper?: Mapper<T, string>): string;
    /**
     * Projects and concatenates the elements of the iterable into a `string` using a separator. This is a resolving operation, will cause a full loop through all the elements of the iterable.<br>
     *   Examples:<br>
     *     * `fluent(['anchor', 'almond', 'bound', 'alpine']).join(', ')` returns *anchor, almond, bound, alpine*
     * @param separator The separator to use in between the elements of the iterable.
     * @param mapper The function which projects the elements of the iterable into `string`s. Falls back to the identity function if omitted.
     * @returns The concatenated string of the elements in the iterable.
     */
    (separator: string, mapper?: keyof T): string;
}
export interface AsyncJoinFunction<T> {
    /**
     * Asynchronously projects and concatenates the elements of the iterable into a `string` using a separator. This is a resolving operation, will cause a full loop through all the elements of the iterable.
     * @param separator The separator to use in between the elements of the iterable.
     * @param mapper The function which asynchronously projects the elements of the iterable into `string`s. Falls back to the identity function if omitted.
     * @returns A promise of the concatenated string of the elements in the iterable.
     */
    (separator: string, mapper?: AsyncMapper<T, string>): Promise<string>;
    /**
     * Asynchronously projects and concatenates the elements of the iterable into a `string` using a separator. This is a resolving operation, will cause a full loop through all the elements of the iterable.
     * @param separator The separator to use in between the elements of the iterable.
     * @param mapper The function which asynchronously projects the elements of the iterable into `string`s. Falls back to the identity function if omitted.
     * @returns A promise of the concatenated string of the elements in the iterable.
     */
    (separator: string, mapper?: keyof T): Promise<string>;
}