2022.42 Grep no Fear

Elizabeth Mattijsen has published an introduction into the Raku Programming Language by means of the grep functionality, called Don’t fear the grepper! (Part 1), the first of hopefully a long series of easy to read, yet in-depth exposition of Raku features. And they also published the second instalment of the It’s time to rak! series, about the rak utility.

Steering Council

The minutes of the October 15th, 2022 meeting are available.

Did You Know?

That you can check whether a key exists in a hash by using the :exists adverb?

my %h = a => 42, b => 666;
say %h<a>:exists;  # True
say %h<c>:exists;  # False

But what if you want to check whether a key does not exist in a hash? A common error is to prefix the lookup with ! (prefix !). Fortunately, that comes with an appropriate error message nowadays:

my %h = a => 42, b => 666;
say !%h<a>:exists;
# Precedence issue with ! and :exists, perhaps you meant :!exists?

Indeed, the way to do this, is to put the negation into adverb itself! So:

my %h = a => 42, b => 666;
say %h<a>:!exists;  # False
say %h<c>:!exists;  # True

Check out the “did you know” registry, started by Wenzel P.P. Peppmeyer. Suggestions as Pull Requests welcome!


Weekly Challenge #187 is available for your perusal.

New Pull Requests

Core Developments

  • Elizabeth Mattijsen fixed an issue with snip and an infinite list of cutting points.
  • Christian Bartolomäus made generics work with return types in signatures on the JVM backend.

Questions about Raku

Meanwhile on Twitter

Meanwhile on the mailing list

Comments about Raku

New Raku Modules

  • Inline::J “Use the J programming language inside Raku” by 0racle.
  • Wasm::Emitter “Emit the WebAssembly binary format” by Jonathan Worthington.
  • LocalTime “A wrapper of class DateTime with varied formatters depending on time zone entry” by Tom Browder.
  • XDG::GuaranteedResources “Guarantees that a resource is present in the expected XDG Base Directory directory” by Kay Rhodes.
  • DateTime::React “Be alerted when clock rollovers occur” by Matthew Stuckwisch.
  • Intl::LanguageTaggish “A role modeling behaviors of a Language Tag” by Matthew Stuckwisch.

Updated Raku Modules

Winding down

Almost more new modules than updates! With some cool new stuff! And don’t forget to think about your Raku Advent Calender blog post!

This week’s picture is showing the beauty of a chestnut tree, to remind us of the beauty of Ukraine, still fighting the Russian aggression. Слава Україні!  Героям слава!

In the meantime, please keep staying safe, keep staying healthy, and keep up the good work!

If you like what I’m doing, committing to a small sponsorship would mean a great deal!

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