[ This is the 100th Item we've shared with you in the two years this blog has been around. We deserve a holiday and we're taking it, so read us next year! Happy Holidays.] Perl 5.10 added rudimentary grammar support in its regular expressions. You could define many subpatterns directly in your pattern, use them [...]
Perl 5.16 makes the Perl special variable, $$, writeable, but with some magic. That’s the variable that holds the process ID. Why would you ever want to do that? There’s not much to write about with this new feature, but there’s plenty to write against it since it introduces more magic (see commit 9cdac2 on [...]
The Perl 5 Porters are currently working on Perl 5.15, the development track that will end up as Perl 5.16. By reading the perldelta515* documentation, you can get a peek at what will mostly likely be in the next maintenance version of Perl. You need to read each of the perldelta5* in a development series [...]
Are you tired of adding the same modifiers to all of your regular expressions? For instance, if you might always add the /u modifier to turn on Unicode semantics on all of your patterns, including qr//, m//, and s///. Instead of remembering to do that to every pattern, the re that ships with Perl 5.14 [...]
Perl 5.10 introduced a flexible method resolution order mechanism. Instead of Perl’s default order (see Understand Perl’s default inheritance model), you can try something less stupid by using the mro pragma to specify which order perl. So far, there are only two resolution orders: dfs, which is Perl’s default depth-first search, and c3, a new [...]
Byte-order modifiers are one of the Perl 5.10 features farther along in perl5100delta, after the really big features. To any pack format, you can append a < or a > to specify that the format is little-endian or big-endian, respectively. This allows you to handle endianness in the formats that don’t have specify versions for [...]
When you’re trying something new, write small programs to test the idea or the new feature. This way, you isolate what you’re doing from the rest of the big application where you might want to use the idea. Some people try to insert the new features directly into the middle of their large programs, but [...]
Perl 5.12 introduced an experimental regex character class to stand in for every character except one, the newline. The \N character class is everything but the newline. In prior versions of Perl, this is the same thing as the . meta character. That is, it’s the same as long as someone doesn’t add the /s [...]
The smart match operator (Item 23. Make work easier with smart matching) reduces many common comparisons to a few keystrokes, keeping with Perl’s goal of making the common things easy. You can use the smart match operator to make even less common tasks, such as matching many regular expressions at the same time, just as [...]
[This is a mid-week bonus item since it's so short] In Perl 5.13.2, you got a non-destructive version of the substitution operator (Use the /r substitution flag to work on a copy). Instead of changing it’s target, the non-destructive version returns a new string that has the substitution. Perl 5.13.7 extends the /r to work [...]
