text: 'use strict';
  
  exports.contains = function (string, substring) {
  	string = String(string);
  	return string.indexOf(substring) !== -1;
  };
  
  exports.hasPrefix = function (string, prefix) {
  	string = String(string);
  	return string.indexOf(prefix) === 0;
  };
  
  exports.hasSuffix = function (string, suffix) {
  	string = String(string);
  	return string.indexOf(suffix, string.length - suffix.length) !== -1;
  };
  