Attributes are a largely experimental feature, still under development, and only present from Perl version 5.6 on....

Subroutines can return values in one of two ways, either implicitly, by reaching the end of their block, or expli....

The subroutines we have considered so far exert no control over what arguments are passed to them; they simply tr....

Basic Perl subroutines do not have any formal way of defining their arguments. We say 'basic' because we can opti....

Subroutines are autonomous blocks of code that function like miniature programs and can be executed from anywhere....

We've not actually plumbed the depths of the regular expression language syntax - Perl has a habit of adding wild....

Now that we've matched a string, what do we do with it? Well, sometimes it's just useful to know whether a string....

We've now moved from matching a specific character to a more general type of character - when we don't know (or d....

Of course, regular expressions can be more than just words and spaces. The rest of this chapter is going to be ab....

Regular expressions allow us look for patterns in our data. We can use that one single value (or pattern) to desc....