text: var isString = require('lodash/isString');
  
  /**
   * Extracts parts of a string, beginning at the character at the specified position,
   * and returns the specified number of characters.
   * The substr() does not change the original string.
   *
   * @customNeeds Validate string type for preventing SyntaxError
   *
   * @since 1.0.0
   * @category String
   *
   * @param {String} string -  The string to extract
   * @param {Number} start -  The position where to start the extraction. First character is at index 0
   * @param {Number?} length -  Optional. The number of characters to extract. If omitted, it extracts the rest of the string
   *
   * @returns {String} Returns extract part of a string
   *
   * @example
   *
   * famulus.substr('Hello World!', 0, 5)
   * // => 'Hello'
   *
   * famulus.substr('Hello World!', 6)
   * // => 'World!'
   */
  function substr(string, start, length) {
      if (!isString(string)) {
          return string;
      }
  
      return string.substr(start, length);
  }
  
  module.exports = substr;
  