Effective Perl Programming – write better, more idiomatic Perl
Perl has some of the best Unicode support out there, and it keeps getting better. Perl v5.32 supports Unicode 13, and you can now apply patterns to character names. You probably don’t want to do that though.
First, the Unicode Character Database catalogs each character, giving it a code number, a name, and many other properties.
Continue reading “Match Unicode character names with a pattern”
Perl v5.32 adds a way to turn off a Perl feature that you shouldn’t use anyway. You can still use this feature, but now there’s a way to take it away from you.
Checking that a value is between two others involves two comparisons, and so far in Perl that’s meant that you’ve had to type one of the values more than once. That gets simpler in v5.32 with chained comparisons. This would make Perl one of the few languages that support the feature. So far its implemented in v5.31.10 and until v5.32 is actually released, it isn’t a real feature.
Continue reading “Chain comparisons to avoid excessive typing”
Perl v5.32 is out and it has some interesting new features. The previous major releases focussed more on finally removing deprecations and shoring up odd cases, and you still find a few of those in this release. Full details, as always, are in the perldelta.
Sawyer X just announced Perl 7 as a major version jump that relabels what is now v5.32. If you’re code is ready for v5.32, you should be mostly ready for Perl 7.
isa infix operator (“class instance”)streamzip program comes with IO::Compress::Base, so it comes with perl"0" .. "-1" is fixed
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This feature is stable in v5.36
Perl v5.32 adds Paul Evans’s infix isa operator—the “class instance operator” as an experimental feature. It still has some issues to work out which prevent its use at the moment, but it looks promising. It subverts how the UNIVERSAL::isa does its job and breaks that in the process. As an experimental feature, that’s fine, but you shouldn’t use this until that’s worked out.
There’s no word on versions for can or does.
One of the delightful things to note about this is addition is that it is one of the features whose development took place almost entirely through a GitHub issue and pull request. GitHub is now the primary repository for the Perl code, and has been since October 2019. This is a feature that I’ll want to use right away in new production code.
Earlier this year, this website was the target of some sort of attack in which a bot sent seemingly random data in its requests. The attack wasn’t that big of a deal since I easily blocked it with Cloudflare, but it was interesting. The apparently random data was actually a mix of Latin, Hangul, and Cyrillic. Domain hacks with unusual Unicode characters shows some of these exploits. Curiously, v5.28 added some regex feature that deals with this sort of nonsense.