... rather than optimize your code at the expense of increasing its complexity, thus making it less maintainable. Caching can also be a big win in providing scalability when you have a bottleneck like ... , text , line , or html . These produce an error message with no trace, a multiline error with trace information, a single-line error with tab-separated fields (suitable for writing to a log), ... first component in the stack. If this method is called with an integer argument, then that number is used as an index number into the stack. Just as with Perl arrays, negative integers start...