Wednesday, March 19, 2008

Screencasts on Smalltalk, Squeak and Seaside

Hello everyone,
During Campus Party, I've met Fabio Akita and he was asking about some demonstration of Seaside and screencasts about it. Seaside is a framework to build web applications written in Smalltalk and whose main name is Avi Bryant (who Akita interviewed in two parts: part 1 and part 2). It is a very neat way of building web applications even easier than Rails. It is mainly used with Squeak that is the most advanced free and open source Smalltalk Virtual Machine.

Being the current teacher assistant for an Object Oriented Programming course at the university, I've decided to launch myself into screencasting about Smalltalk, Squeak and Seaside to attend Akita's request. The first one has just been recorded but was aimed to the students so it is in portuguese and speaks about Morphic, the main user interface for Squeak. You can see it at (requires java browser plugin installed):
http://www.screencast-o-matic.com/watch/cjeFrOV2c
Or download it in an MP4 47 Mb file (requires some free codecs) at:
http://eclipse.ime.usp.br/~night/00-morphic-800.mp4
or
http://www.ime.usp.br/~kon/MAC5714/00-morphic-800.mp4

I've found this new feature in blogspot to upload a video. Trying here:


I pretend intend (thanks Kenzo) to release another version of it in english for those interested in it but I will wait for some feedback to correct and improve the current version.

It requires that you have Squeak installed and running which can be easily done by downloading the correct package for your operating system at http://www.squeak.org/. Click your operating system link on the top right side of the site to download squeak (the virtual machine) and a clean image of Squeak's world.

Smalltalk is slightly different than most current object oriented languages. The Squeak Image (.image file and .changes) is a representation of Squeak's world as it was on last save. This means when you load it, it is just like if you were back at the exact time when you saved your image. The same things are showing, same processes are running, same everything. Especially this means, if you screw up your image and save it, closing and opening won't help at all. Therefore, create backups of your .image (and .changes) every once in a while.

Then you can do some very fun things such as changing the behaviour of the True class (in Smalltalk, there is no syntax specific word... EVERYTHING is a class, even conditionals and loops but we will see about that in another screencast).

For now, I'll leave you, non-portuguese speakers, testing squeak by yourselves (although the speaking is not THAT important in the screencast) and the others, have fun creating games for your kids!

bye bye

3 comments:

Kenzo said...

Hugo, seria "intend" ao invés de "pretend", não?

Abraços!

jarober said...

I have a whole series of screencasts on Cincom Smalltalk (including a number on Seaside) her:

http://smalltalk-daily.cincomsmalltalk.com

Hugo "NighT" Corbucci said...

@kenzo

Tá certo. Corrigido! Brigado
That's right. Corrected! Thanks

@jarober
Great! I've added the link to your blog to the course material and to the end of the post. Thanks!