PragDave

Ruby 1.9.1 Preview 1 is out

The path to a stable Ruby 1.9 has been long. Almost a year ago, 1.9.0 was released. This turned out to have been less than stable. The core library has grown by many hundreds of methods since then. And, probably more significantly, people have started using 1.9 for real, and they've discovered rough edges that needed to be fixed. In particular, the multinationalization support, which is incredibly ambitious, turned out to be hard to use for library writers. James Edward Gray II was probably the first to bump into this as he updated his FasterCSV library (now part of core Ruby) to handle any encoding supported by Ruby. His problems lead to a lot of discussion, and eventually to an entirely new concept inside the interpreter. And as a result, the core team have decided to slip the release of 1.9.1 by at least a month while they investigate other encoding-related issues lurking in the libraries.

In the meantime, a 1.9.1 preview has been released. Details are here.

If you are the maintainer for any publicly available Ruby code (be it a Gem, an application, or whatever) I strongly urge you to download this preview. You'll be doing the community a great service in two ways. First, the various incompatibilities between 1.9 and 1.8 mean that there's a chance that your code may not work without some tweaks. Making those changes now will help others using your code. As importantly, by using 1.9.1 for real, with real code, you'll potentially discover other rough edges. Reporting these back through ruby-core or RedMine will help the Ruby developers further hone the interpreter.

Now, all this delay leaves me with a problem. The new 1.9-specific PickAxe is now content complete. Some people have been waiting for it for 10 months. And I have to decide: should I hold on for the official 1.9.1 release (which will be, at the earliest, at the end of January 2009) or should I send it to the printers? Let me know what you think.

Fun with Ruby 1.9 Regular Expressions

I've reorganized the regular expression content in the new Programming Ruby, and added some cool new advanced examples. This one's fairly straightforward, but I love the fact that I can now start refactoring my more complex patterns, removing duplication.

The stuff below is an extract from the unedited update. It'll appear in the next beta. It follows a discussion of named groups, \k and related stuff.

---

There’s a trick which allows us to write subroutines inside regular expressions. Recall that we can invoke a named group using \g<name>, and we define the group using (?<name>...). Normally, the definition of the group is itself matched as part of executing the pattern. However, if you add the suffix {0} to the group, it means “zero matches of this group,” so the group is not executed when first encountered.

sentence = %r{ 
    (?<subject>   cat   | dog   | gerbil    ){0} 
    (?<verb>      eats  | drinks| generates ){0} 
    (?<object>    water | bones | PDFs      ){0} 
    (?<adjective> big   | small | smelly    ){0} 

    (?<opt_adj>   (\g<adjective>\s)?     ){0} 

    The\s\g<opt_adj>\g<subject>\s\g<verb>\s\g<opt_adj>\g<object> 
}x

md = sentence.match("The cat drinks water") 
puts "The subject is #{md[:subject]} and the verb is #{md[:verb]}"
 
md = sentence.match("The big dog eats smelly bones") 
puts "The adjective in the second sentence is #{md[:adjective]}" 

sentence =~ "The gerbil generates big PDFs" 
puts "And the object in the last is #{$~[:object]}" 

produces:

The subject is cat and the verb is drinks 
The adjective in the second sentence is smelly 
And the object in the last is PDFs 

---

Cool, eh?

The iPhone Book is in Beta!

We've heard back from Apple. We've double checked with the authors. And the iPhone book is in beta.

After a rocky start, I have to say we've had nothing but help and support from folks in Apple. And eventually the senior management listened to the community and did the right thing. Thanks to our friends in Apple for their help, and thanks to everyone for your support and patience.

Enjoy the book. And write some killer iPhone apps.

Dave

The Apple NDA is lifting...

A great huzzah! was heard through the land. Apple today announced that they will be lifting the NDA on the iPhone SDK. This is incredibly good news, as it means that, once lifted, developers will be able to talk with each other about the iPhone. And, among those developers are those that have created iPhone content for our Core Animation and iPhone SDK Development Books, a screencast series on iPhone development, and a brand new Pragmatic Studio on iPhone Development. All of these have been sitting here, waiting to get released.

So, all day I've been getting calls and e-mails saying “The NDA is lifted. Where are the books?” The answer is simple: right now the NDA hasn't been lifted. Apple have announced that they will be dropping it, and that a new developer agreement will be sent out within "a week or so." Our developers are still apparently bound by the existing NDA.

So, I spoke with someone senior at Apple this morning, and I'm waiting to hear back. In effect, the NDA is dead. But I need to protect our authors, so we can't release any iPhone content until we hear back that they're out of danger.

I'll blog here when I know more. We'll also send out an e-mail to our announcement mailing list and RSS feed.

Interesting times...