Recently, Anthony Ferrara has been posting a periodic "Beyond" series about software design philosophy. Some in particular have hinted at concepts I've been pondering as well. With his blessing, therefore, consider this a continuation of that series.
PHP 5.4 is not exactly new, but it's finally starting to see actual usage by a decent number of people. Its most notable new feature is Traits, which in PHP are implemented as, essentially, compile-time copy-paste. Conceptually, though, they're a way to mix functionality into a class without using inheritance, and without requiring a separate distinct object for composition. (At least in PHP; the term "trait" appears in other languages for similar but subtly different tools.) That's not to say that they're a surrogate for composition; they most certainly are not. They serve a different purpose, that is, providing code for a class to reuse without using inheritance.
Recently, I was reading an article discussing the implementation of inheritance, such as it is, in Go, Rust, and other new-wave concurrent languages. (Thanks to twistor for helping me track down the link.) It made an interesting point that crystallized for me why it is I am so excited about traits. Specifically, it noted that there are not one but two kinds of code reuse: interface reuse and code reuse.
Recently I had an email conversation with someone about PHP, and how to market a new product to PHP developers, specifically through getting major PHP projects to adopt it. The details of that conversation are not really relevant, but in the course of the discussion a familiar topic came up that I feel warrants a blog post of its own.
There is a schism in the PHP community. A big one. One so big that I don't think many realize it's there, because the gulf across it is just so wide. See, there's not one "thing" called a "PHP Developer"; there are two, and they are so unalike that I have never seen them really see eye to eye.
A little over a month ago, a few Drupal developers announced something new: A fork of Drupal called Backdrop. There's been quite a bit of talk about it, of course. While I don't plan to be using it myself, Backdrop has raised a number of valid points and criticisms of Drupal that are worth discussing.
Well, I've gone and done it. I've managed to setup my most intense conference schedule to date. This fall I will be appearing at no less than five conferences, speaking at least four of them.
If you're into Stalking Crell, here's where you'll find me around the globe this fall.
You can either get on the Drupal 8 bus now, or get run over by it later.
It's true. Drupal 8 is coming, and it will be big. Not just lines of code (that too), but big in the sense that Drupal 8 changes more of Drupal than any major release in the last 10 years. The adoption of so many 3rd party components (from Symfony and otherwise) is only part of that picture. That offers challenges for many, but also enormous opportunity. Drupal 8 will allow Drupal to expand into new types of application and new markets, which is a great thing for those who make their living off of Drupal. But where do you get started with learning about Drupal 8?
At DrupalCon Portland, that's where!
There are many sessions slated for Portland at both DrupalCon and at Symfony Live that deal with Drupal 8, either directly or indirectly. Below is my recommended hitlist for Portland for those wanting to get the lowdown on Drupal 8.
What, you're not already signed up? There's still time! Go register for either DrupalCon or Symfony Live, and be sure to get a Combo Ticket so that you are able to attend both conferences as well as Web Visions! (The combo ticket is the same price either way.)
Earlier today, I posted a brief tweet (isn't that redundant?) about return values in PHP (or really, any language). Originally it was about return values from functions (such an exciting topic, I know), but it ended up generating a fair bit of lively conversation, as well as a patch against Drupal 8. So lively, in fact, that I think it deserves more than 140 characters.
If your function returns a collection, its null value return must also be a collection.
And so 2012 draws to a close. The world didn't end, to the disappointment of many. In some ways it was an eventful year, in others rather ho-hum follow-ups to the excitement of 2011.
In the Drupal world, though, 2012 will go down as the year Drupal finally began replacing NIH with PIE. Compare Drupal's 8.x branch a year ago with it today. A year ago, we had one class of 3rd party PHP code, in an uninteresting corner of the update system. Today, it contains 3rd party code from no less than five different projects: Symfony, Doctrine, Guzzle, Assetic, and Twig. Those libraries are included via Composer, the new and ground-breaking PHP-library-management-system-that-actually-finally-works. Code from at least one more should be landing soon.
Drupal developers, working on Drupal, have contributed to a number of other projects, including Symfony and Symfony CMF, and because of the degree of code sharing happening in the PHP world now have indirectly contributed to a half-dozen other major projects, too. Drupal 8, aside from the technological advances it will offer over Drupal 7, also represents perhaps the largest cultural shift in Drupal or PHP history.
Are you ready for 2013, Drupal? Really?
The private variables debate is going around the PHP world again. Brandon Savage posted a pair of articles pointing out the perils of private variables, boiling down mostly to them making extension infesible or impossible. Anthony Ferrara replied with his own article, arguing that the real problem is using inheritance in the first place rather than composition. I figured I'd weigh in on my own blog rather than in a comment. :-)
As an academic matter, I agree with Anthony. Composition and interfaces are more flexible than inheritance. I've been preaching the interface gospel within Drupal almost as long as I've been preaching Dependency Injection.
For Drupal 8, we want to bake REST support directly into the core system. It's unclear if we'll be able to go full-on hypermedia by the time we ship, but it should be possible to add via contributed modules. For the base system, though, we want to at least follow REST/HTTP semantics properly.
One area we have questions about is PUT, in particular the details of its idempotence requirements. For that reason, I'm reaching out to the Interwebs to see what the consensus is. Details below.
After a bit of a delay, all slides from my trio of DrupalCon Munich talks are now online. The videos have been up for a while.
See you at the next conference!