/**
 * returns the substr from a larger word
 *
 * @remarks
 * It takes 3 arguments
 *
 * strSub(<word\>, <start\>, <size\>)
 *
 * - **<word\>** - a string
 * - **<start\>** - the start position as a number
 * - **<size\>** - the number of characters to take, as a number
 *
 * ## Usage
 *
 * - `strSub('this is a word', 1, 2)` - returns 'hi'
 *
 */
import { BaseMethod } from './_Base';
export declare class StrSubExpression extends BaseMethod {
    static required_arguments(): string[][];
    process_arguments(args: any[]): Promise<string>;
}