Navigator 2.0, Internet Explorer 3.0
The toString() method of the Function object converts a function to a string. In Navigator 2.0 and 3.0, it returns a string of valid JavaScript code--code that includes the function keyword, argument list, the complete body of the function, and so on. In Internet Explorer 3.0, the toString() method returns a string that identifies the function but that does not include the JavaScript code that constitutes the function.