Apr 10

App Engine with Ruby, Python, and Perl

Comic, Perl, Python, Ruby, Tech with tags: 9 Comments »

App Engine with Ruby, Python, and Perl

Since I am still in London, my sarcasm quotient extends just a little more than usual (it’s pretty high in the US to start with, even if it is the “lowest form of humour”).

I had a fair amount of email from people, and saw some blogs, complaining about the fact that Google App Engine currently supports Python only. On the video, and in the docs, it is frequently mentioned that other languages are to come, and that the infrastructure itself is language neutral. We have to start somewhere!

I personally have a slight Ruby preference, but there is a funny thing about Python. Hardly anyone really hates it. It may not be the language of choice for many people, but a lot of people are telling me:

  • Ah, was hoping to try more Python
  • I was looking for an excuse to code a Django app
  • I can deal with that. Thank god you didn’t force Java

This is a little like the iPhone SDK being Objective-C. People are picking it up. I think this happens then your desire to play with the new toy is greater than your religion!

I am very excited to see more languages and features on Google App Engine, but I know that I just have to be a bit patient, and in the meantime, I had been looking for an excuse to code a Django app.

Feb 13

Interview Day: Perl

Comic, Perl, Tech with tags: 1 Comment »

Interview: Perl

How would you write this regex… using less than 12 characters

What about the other languages?

Got some good ones for other languages like Fortran, BASIC or assembly?

Jan 05

Larry Wall: Programming is Hard, Let’s Go Scripting…

Perl, Tech with tags: , , No Comments »

Larry takes a high level view of the past, present, and future, to create a case for Perl 6.

I hope the future isn’t so far out that Will Smith is the only person alive to see it…. along with some Zombies.

Scripting

But basically, scripting is not a technical term. When we call something a scripting language, we’re primarily making a linguistic and cultural judgment, not a technical judgment.

I see scripting as one of the humanities. It’s our linguistic roots showing through.

Declarational

In Lua, an object is just a hash, and there’s a bit of syntactic sugar to call a hash element if it happens to contain code. Thats all there is. They don’t even have classes. Anything resembling inheritance has to be handled by explicit delegation.

Prototype vs. Class

Real organisms just copy their DNA when they reproduce. They don’t have some DNA of their own, and an @ISA array telling you which parent objects contain the rest of their DNA.

Functional or object-oriented

Of course, some of us can’t make up our minds whether we’d rather emulate the logical Sherlock Holmes or sociable Dr. Watson. Fortunately, scripting is not incompatible with either of these approaches, because both approaches can be made more approachable to normal folk.

Sep 25

War of the Web: Revenge of the Dynamics

Ajax, HTML, Java, JavaScript, Lightweight Containers, Microsoft, PHP, Perl, Ruby, Tech, UI / UX, Web Frameworks 933 Comments »

As I was watching “24 hour party people” on DVD, I heard the main character talk about the ebbs and flows of the music business. He is talking about the scene in Manchester at the end of the 70’s, and into the eighties. Moving from Joy Division to Happy Mondays and New Order.

I think that we are in a new chapter for the web, and as is often the case, the wheel of time is repeating history for us.

There are a few dimensions to the current war though. They are on the client side (DHTML Ajax vs. simple HTML vs. Flash/PDF vs. XAML) and on the server side (Rails vs. Java vs. PHP vs. .NET).

Let’s start at the beginning.

Perl: Birth of CGI

Do you remember how the web changed as it moved from static HTML connected content to dynamic websites? That came about due to CGI, and how our nice web server would now fork off our programs to generate the HTML.

I remember my first CGI programs were written in C, and Scheme. I quickly moved on though, and found the beauty, and craziness of Perl.

I spent quite some time with Perl, trying to get by without writing too much NSAPI and ISAPI code (oops, I guess that core dump hurts the entire server?).

I really enjoyed the community at that time. #perl was interesting (some of the time), and CPAN became the holy grail. As soon as you thought you needed something, someone had kindly put that functionality up into CPAN. I even have some of my own modules hanging out there, and helped with others.

Over a short time period, we had developed some fairly rich web modules. We didn’t have to work with $ENV{’SOME_CGI_ENVIRONMENT’}, or STDIN or the like. Our framework abstracted all of that for us, and gave us a simple model. We lauched at the folks who generated html via methods such as b("whee") and we stuck close to HTML itself, allowing our design teams to simply open the html files and see what their stuff looked like. We even had the notion of components, and special tags that you could create. <$mytag name=”…” /> was nice because the name of the tag was the key for the framework to dynamically discover that functionality. No config files, or interfaces, in the strict sense. The coupling was based on a name.

In retrospect, life was pretty simple for web development, a lot simpler than some of the frameworks we have today!

But, we moved from Perl. CGI was not the nicest for our high load servers. It was crazy to think that we would fork a process for every little request that came in, and that a Perl interpreter would start up, load the program, do the work and then die off.

We naturally moved to solutions such as mod_perl, and that helped. It was so new though that it was buggy and we had a lot of problems. Some of the problems had nothing to do with mod_perl itself, but due to laziness and side-effects.

When you work in an environment like CGI you can be a very bad man indeed. If you don’t close something correctly, or don’t play totally nice with resources, baaaah who cares? The server is going to kill me in 2 seconds anyway, so I will get my job done and have him kill me. In mod_perl world though, these programs start to live longer, and they get fat and oily.

Java: No more stinking processes!

Remember the beginning of Java (Oak!). We were building applets, and feeling the pain very early on.

Servlets were the big thing though. We ported our Perl based framework over, and were able to see significant performance improvements at the time. Some of the team loved the change, others hated the verboseness and static typing.

The nice threading model that Java gave us was huge though, even with the poor JVMs back then (Microsofts was by far the best remember!).

This is when we moved from the world of Perl to having Java start to take over. That isn’t to say that there wasn’t competition. In the waters we saw the lurkers of ColdFusion, ASP, and the beginning of the PHP revolution. Java came up with JSP to compete with these tag based approaches, but it was the advent of the rich MVC style frameworks that really spurred everyone on.

In my opinion Java is still in the hot-seat, especially in the corporate world.

Preparing for the server war

The troops are being gathered. Strategies are being worked out. We are currently getting ready for a new battle on the server side.

What’s happening?

  • Ruby on Rails: Whatever you think about Rails, it has lit a fire under the server side web development community. Many have jumped on the bandwagon, claiming real productivity improvements. Some of the PHP converts enjoy a richer language, which is still nice and dynamic, with a framework that enforces clean MVC techniques. Some of the Java community are frankly a little bored of Java, and enjoy the new challenge. They also love the freedom of the language, and the fact that they now have just ONE stack to worry about. Will the Rails buzz keep growing? Will it be the Perl of Web 2.0?
  • Java: Java isn’t going down without a fight. Some argue that the problem with web development in Java is that it has been too complicated and heavy for much usage. I have personally called for the need of a common stack for Java, and people have stepped up to the plate. On one side we have companies that will certify a set of technologies (JavaServer Faces + Spring + Hibernate). Then we get frameworks taking on simplicity themselves (WebWork now embedding Spring). Finally we have initiatives like JBoss Seam, which is trying to combine the component models of JavaServer Faces and the backend. Seam aims to give you the power of the Java tier, but also giving you a simple productive environment. So, Java frameworks are rising to the challenge of Rails, and we will soon see how much of the success of Rails is Ruby, and how much can be duplicated in other platforms.
  • PHP: We can’t discount PHP. A lot of “serious engineers” (read: anyone who isn’t a PHP developer thinks they are serious) poo poo the PHP world. Yet, by all accounts, there is a LOT of PHP development going on out there. PHP has the advantage of being something written JUST for the web. Take a look at how Wordpress came along (PHP based blogging software) and in no time at all there were thousands and thousands of plugins that you could simply drop into your Wordpress system. Literally, you drop in a file and you are done. There are numerous PHP frameworks that are aiming to mimic, and compete with Rails, so we can’t forget about these guys. The question with the PHP community is: will it grow more into the enterprise, or will it be for script-kiddies.
  • .NET: Never discount Microsoft. ASP.NET keeps getting more productive, and it is hard to compete with their end to end story, which includes fantastic tooling in their latest Visual Studio. And, we get Avalon and XAML along for the ride, as well as the futures of C# 3.0 which takes a lot of ideas from the dynamic languages and puts them into a static structure (such as: var foo = new Bar(); and the relational/xml integration)

It is going to be an interesting couple of years, as all of these platforms mature, and take eachother on, trying to get mindshare!

Client Side: JavaScript is cool again

But what about Ajax? The battle for the client side is going to be just as hot as on the server. And they will even intertwine with eachother.

Firstly we have the big debate of how far Ajax is going to go. Is it a one hit wonder? or will it become a standard part of our toolbox and even just be called dhtml again?

As an Ajaxian, I obviously have my thoughts on this matter. But there is a lot of competition inside and outside of Ajax:

  • Flash/PDF: Adobe/Macromedia are a definitely force to be reckoned with. Flash is almost ubiquitous, and PDF is used everywhere. Now the companies are combined, what do they have in store for us?
  • Avalon/WPF/E/XAML: Microsoft announced WPF/E, which is a subset of XAML that will be ported on various platforms and available in many browsers. This means that you can build your rich application in the .NET set of tools, and have it run in Safari on Mac OSX. Impressive. When are we actually going to see this in a form that we can deploy to the real world?
  • HTML: How much do we want to work in the open (ish) world of HTML. A large group of developers do not want to jump into any monopoly, and will therefore want to stick to a more open environment. But, another set will just want to use the best tool to add business value. What will the split be?

JavaScript will play a big role in this war. JavaScript 2.0 offers big improvements, that many people will cheer for. Also, the same people who poo-poo’d JavaScript in the past have come to realise that it really is a great language. It may not be what they are used too (it uses prototype-based OO vs. class-based OO), but it is powerful and robust. There are some features missing, and a big question around libraries. JSAN and others are trying to build a CPAN for JavaScript. We also worry about the black box of the JavaScript VM in the browsers, and cross-browser bugs are truly real painful. Fortunately, frameworks like Dojo and Prototype are trying to help us out on that front.

We are also seeing that we need to take JavaScript from the former:

“That is just crappy code that the web dood View-Source’s and pastes into the web pages”

to the future:

“JavaScript also needs to be engineered, and is a first class citizen”

Thus we finally see more unit testing of JavaScript code, and professional ways of creating modules and namespaces for our code. We also see great advantages with features like E4X where XML becomes a native type.

JavaScripts increased popularity, thanks to Ajax (and Flash/ActionScript) has also drawn it into the server side. Mozilla Rhino gives you a quality Java-based approach, so why not use a cool dynamic scripting language for certain tasks on the server side? You don’t have to use JavaScript for everything, but it has its place, and that place is growing.

The Battles Join

This is where the battles are joining. We have JavaScript bleeding across the layers, and we have the need for server-side frameworks to support the new Web. It isn’t enough to generate simple HTML and be done with it.

Today’s frameworks need to be able to help us build Ajaxian components, and help us write this applications quickly and cleanly.

There are various directions that frameworks are going in here.

  • JavaScript Code Gen: Why not give you a simple macro that splits out the ugly JavaScript that you would have to write?
  • JavaScript Framework Code Gen: Spitting out low-level JavaScript is too much work. Many frameworks are writing on top of a higher level JavaScript framework like Dojo or Prototype. Now the code-gen is less, and you get the benefits of the rich functionality, browser compatibility, and visual effects available from these frameworks.
  • Tools and Widgets: Should developers even care if a piece of their page is Ajax or not? Some frameworks give you drag and drop editors that let you setup widgets or components. Some happen to be ajaxian. Some are not. Who cares?
  • Markup based: A lot of frameworks are giving us markup based solutions. That is one of the strengths of Microsoft Atlas, not the fact that they added support for $() etc. Are we going to want to build using markup or via programatic APIs?

Conclusion

It is hard to predict the winners of the new battles, and the losers will not die off totally, but it is an exciting time to be watching web development. The dynamic languages of Ruby, JavaScript, and PHP are making a big run, and people are realising that they aren’t just cheesy scripting languages that can’t be used. It’s time to take them serious.

We are going to start really working out what makes sense for usability on the web with rich interfaces. And, at the same time we will get simpler and simpler backend tools to make the generation of rich web experiences easier and easier.

I am looking forward to seeing this battle!

Aug 23

Write PHP in Perl with PHP::Interpreter

PHP, Perl, Tech 72 Comments »

Ever written a Perl application and wished that you could write some PHP in there? Ok, probably not too often…. but now you can!

This came about via Bricolage Now has PHP 5 Templating and how:

And finally

Aug 03

Perl 6: Endgame?

Perl 4 Comments »

Alasdair Allan went to hear from Damian Conway and Larry Wall promise that Perl 6 is going to happen. Honest.

Although it is very interesting to hear the Apocalypses and Exegenesis’ come to us over the years… I am actually a little more interested in Parrot.

I hear you all laughing out there. Parrot? That crazy Perl 6 VM toy?

It could end up academic, but having a cool VM built for dynamic languages is interesting. It could be the perfect VM for Ruby 2…. as well as many others.

Sure, my ideal would be to have all of these languages running on the JVM like Rhino and Groovy (JRuby… you can get there!), this would be a second best. And, with a nice bridge Parrot and the JVM could play together.

Ok, I know I know…. I am kinda out there.

Jun 23

Perl Best Practices

Perl, Tech 1 Comment »

I know:

  • Some people think that Perl Best Practices is an oxymoron
  • Some people think there is one best practice: Use Ruby/Python/[insert your language of choice here]

However, the title of this upcoming book will really peeve Ted since he hates the term Best Practices so much :)

Also, on Sunday, there were 3 simultaneous

Apr 12

Caller context and list.add(..).add(..).add(..)

Java, Perl, Tech 12 Comments »

One of the first things that bugged me about Java when I first started to use it was a small thing. Why didn’t add() return the list (or Vector back then) so I could chain the calls together.

I wanted to be able to:

Vector v = new Vector().add(”foo”).add(”bar);

The same goes for having chained set* methods:

foo.setA(a).setB(b)

We see this used, especially in certain packages such as Hibernate.

One feature that I liked in Perl was the ability to know about the callers context:

my $scalar = @list; # or function which returns a list

is very different to:

my ($element) = @list; # or function which returns a list

Sometimes I would love to do the same in this world and say “If the caller of my set method wants the object back, give it, else we are in void world and that is fine too”.

Of course, I don’t think this would happen :)

Another way to make me a little more happy would be to give me named parameters, but that doesn’t give me the same power.

Feb 25

Pugs: Perl 6 interpreter in Haskell

Perl, Tech 8 Comments »

All I can say is “wow”. Autrijus has written an interpreter for Perl 6 in Haskell called Pugs. Kudos.

Oh, and here is a small example of some Perl 6 code:

#!perl6
use v6;

multi sub quicksort ( ) { () }

multi sub quicksort ( *$x, *@xs ) {
my @pre  = @xs.grep:{ $_ < $x };
my @post = @xs.grep:{ $_ >= $x };
(@pre.quicksort, $x, @post.quicksort);
}

(1, 5, 2, 4, 3).quicksort.say;
Sep 20

RE: It’s not about one-liners

Groovy, JavaScript, Perl, Ruby, Tech 3 Comments »

I agree with Cedric.

The “best” programming language, doesn’t mean the one that creates the lowest wc -l.

I actually always found myself writing quite “verbose” Perl code, for example.

However, I do feel that languages such as Ruby, Groovy, and yes… even Perl allow me to get closer to the zen of “expressing everything I want, and need to get across… but not more”. Every operator/method tells me a lot.

For example. Compare the code for taking out some text from a string:

Groovy:

name = “Dion ‘Sick Boy’ Almaer”
name -= “‘Sick Boy’”

and in Java? ergh.