Updates to chapter 17, “Advanced Topics”

[This post notes differences between the fifth and sixth editions.]

Chapter 17 of Learning Perl is a catch-all chapter at the end of the book. We cover some “advanced” items to pique the interest of the reader and to segue into Intermediate Perl. Mostly, this covers grep, map, and eval.

Since we also cover Perl modules, we expanded this chapter a bit. The list operators are nice, and since list operations are most of many programs, so we should at least mention List::Util and List::MoreUtils.

The eval is the minimum for dealing with errors, and it also provides quite a bit of trouble as it handles $@. So, we also introduce Try::Tiny. We don’t say much about it, but anyone who makes it this far at least finds out that it exists. While we are at it, we might as well throw in autodie, especially since it’s part of the Standard Library.