Let's say you want an attribute to accept a pair of numbers - perhaps a geographic co-ordinates [ 50.873, -0.002 ]. You could constrain the attribute as ArrayRef[Num], but that would accept an arrayref containing a single number, or eight numbers, or even a reference to an empty array.
With the Tuple type constraint, you can be more exact in expressing which values are acceptable:
isa => Tuple[ Num, Num ]
We are hoping to live stream the conference which starts on Friday morning. We will have streams of all three tracks:
Hall Vitosha
Hall Musala
Hall Rodopi
Hope you can join us!
[ Cross-posted by invitation, from its home on the Ocean of Awareness blog. ]
Currently, in designing languages, we don't allow ambiguities -- not even potential ones. We insist that it must not be even possible to write an ambiguous program. This is unnecessarily restrictive.
This post is written in English, which is full of ambiguities. Natural languages are always ambiguous, because human beings find that that's best way for versatile, rapid, easy communication. Human beings arrange things so that every sentence is unambiguous in context. Mistakes happen, and ambiguous sentences occur, but in practice, the problem is manageable. In a conversation, for example, we would just ask for clarification.
So you have this Moo class, and it turns out what you really need for it is the StrictVersionStr type constraint defined in MooseX::Types::Perl. You could switch the class to Moose, but long term you want to stick with Moo.
Eventually you'll steal what you need from MooseX::Types::Perl, so you don't have the Moose dependency, but for now what you really want is to be able to use a Moose type constraint within a Moo class! What a predicament you've gotten yourself into! Type::Tiny to the rescue!
{ package Local::Eg5; use Moo; use MooseX::Types::Perl qw( StrictVersionStr ); use Types::TypeTiny qw( to_TypeTiny ); has version_number => ( is => "ro", isa => to_TypeTiny( StrictVersionStr ), ); }
It turns out that it’s quite hard to change Ukrainian Hryvnia back into your local currency. Apparently you need to get a special form to do it, which seems to be about as common as a Ryanair refund.
Given that quite a few of us aren’t that likely to return to Ukraine any time soon, it implies that there’s quite a lot of paper money sitting around various Perl monger’s desks, drawers etc, not earning its keep. For each individual it’s not much in value, but I suspect that all together it adds up to a few thousand Pounds/Euros/Dollars etc. Meanwhile, the Ukrainian central bank is very happy about all currency it got in return for selling us [its] bits of paper.
So I thought that it would be a good idea if we put the notes carefully to one side, and then all took them to Sophia next year, where at YAPC::Europe 2014 someone from Kiev can come with a big bucket, collect the money, and take it back to do useful things with it.
I assume that the intervening events have not made changing the currency any easier…
In any case I’ll be bringing my 70 along, and bulk88 has expressed interest to buy, should none of our attendants from the Ukraine want them.
Sometime in May 2014, ETHER mentioned on IRC that she would soon be passing me up on this leader board. I was number 20 and she wasn't far behind. I guess I took that as a challenge, because this past weekend on CPAN day, I moved into the #6 spot. This post explains how.
I've created a couple CPAN packagers over the years, like Module::Install, and Module::Package, but earlier this year I decided to give up on those and just use Dist::Zilla, so I moved most of my active stuff to that. In the past year, as an Acmeist, I started doing a lot of real programming in Bash, and recently I made a Bash-heavy wrapper around Dist-Zilla called Zilla-Dist.
Yesterday (August 16th 2014) we celebrated the anniversary of the first upload to CPAN by Andreas König (ANDK) (as he worked on what became PAUSE). It was the 19th anniversary, but the first that we've marked in this way.
In one day, 107 people uploaded 775 releases, 41 of which were the first uploads of new distributions, and 10 of which were the first upload by new CPAN contributors. The first two numbers were outright records, and the second equalled the previous best. All of those numbers were higher than I expected.
Here's a quick way to create an attribute that coerces to an integer from any other number:
package Local::Eg3; use Moose; use Types::Standard -types; has foo => ( is => "ro", isa => Int->plus_coercions( Num, sub{int($_)} ), coerce => 1, ); __PACKAGE__->meta->make_immutable;
I didn't think it was a contest but I think Ingy won CPAN Day....
Mark eting may prefer vampires, but here's a different why Kephra keeps evolving, for all that are interested in dev tools, written in Perl. Oh , btw, it go ready on CPAN day - mere coincidence. :)
First off, let me say I think CPAN Day is a great idea, and I am happy to take part in it!
For CPAN Day, I have contributed App::HTRender, a command line tool to assist development of HTML::Template-based templates. If you are building a website using HTML::Template and your data model is still fluid (or you just want to quickly test different values) you can lay out your data in JSON format and use the ht_render command to feed it to your template without having to change any of your Perl code.
Additionally, Logical Helion has released a new version of Helios, Helios 2.81. This version is largely a bugfix release, but does include a new command for retrieving jobtype information and some improvements to the helios_config_* commands.
Happy CPAN Day everyone!
When you use code like this:
package Local::Eg2; use Moose; use Types::Standard -types; has foo => ( is => "ro", isa => Int, coerce => 1, ); __PACKAGE__->meta->make_immutable;
Perhaps you don't think very much about what that bareword Int is actually doing. Well, it's a function that returns a blessed object. This object is used by Moose to check whether values are integers. Yes, Moose uses the object, and you can use it too!
On request of Neil Bowers i pushed this release back a day, so now on CPAN Day in 2014 the first update of PPI in 3.5 years has been released to CPAN and will be available on a mirror near you soon.
Since the release candidate only minor changes affecting the release process itself have been made.
The change log has a detailed listing and the git repository is even more detailed (it even has tags if you clone it). That said, the summary of the changes is:
My project for CPAN Day has been to pull together a history of CPAN:
In best CPAN tradition, this is the work of dozens of people, who patiently responded to my pestering via email over the last few weeks. Thanks to everyone who helped get it to this point.
To celebrate CPAN Day, NEILB and BOOK are proud to announce a new CPAN-related site, specifically targetted towards playing with CPAN (with the underlying goal of improving it).
Please join us in celebrating the first the day of cpan.io!
The site is rather empty now, but we have grand plans for it. Come play the CPAN game with us, fork cpan.io on github and send us patches and feature requests.
Type::Tiny objects overload the & (bitwise and) operator to build a type constraint intersection. For example:
package Local::Eg1; use Moose; use Types::Standard -types; has foo => ( is => "ro", isa => ArrayRef[Int] & HashRef[Int], ); __PACKAGE__->meta->make_immutable;
Though that example isn't especially useful. Do you remember Venn diagrammes? Intersections are that small overlapping section in the middle. So the value for foo needs to be something that is simultaneously an arrayref and a hashref. (Which no value could satisfy.)
But there are ways intersections can be used more usefully.
Lately there has been a buzz of activity in the Test-More project (Test::More, Test::Simple, Test::Builder). In fact, it is safe to say that very little code has gone untouched in this process. We are currently on the 34th alpha release of the new Test::Builder, and I wanted to take a moment to discuss the things that are happening!
This is the first of several blog posts that will cover the changes to Test::Builder. This one covers the "why".
Why are things changing? The simple answer of course is "Testing". A more helpful answer is this: Test::Builder is the de facto standard when you go to write a test. Just about any testing tool you use will rely on Test::Builder under the hood. The problem though, is that testing your testing tools is still somewhat archaic.
Currently, if you want to test a test library, you have two choices:
Test::Builder::Tester
Test::Tester
While I know many of you have CPAN Day projects, some of you might still be searching. There is a very well known benchmark from TechEmpower which compares web frameworks. It gets plenty of press and generates much interest. Unfortunately, the Perl results look like this:
We all know the reputation that Perl has to the outside world, and sadly these results would tend to reinforce it. The person or persons who added these apps seems to have long since forgotten about them. At least the Mojolicious app was a port of one of the others and did not exemplify either the style or power of the framework. The others likely share those traits.
But all is not lost! TechEmpower has recently made it much easier to contribute, and I have fixed the deployment and toolchain problems. I have also updated the Mojolicious app. Would you like to improve the submission of your favorite framework or add your own? Read on!
CPAN Day (August 16th, UTC) is nearly here. Someone asked me what the goals are, if any, for CPAN Day. When BOOK came up with the idea, we both thought it was an opportunity to celebrate CPAN, but also a chance to reflect on how we got here, and to think about how we can keep driving it forward.
I also saw it as an opportunity to bang on my curation drum — give everyone ideas for how they might improve their distributions, or those of others, and in doing so improve the overall quality of CPAN.
CPAN was created by us, for us, so do whatever feels right to you.
If you do something for CPAN Day, please tweet about it with the #cpanday hashtag.
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