What is Squeak
Squeak VM Download
The Class Image
What is Squeak?
Squeak is a modern, open source, highly portable, fast and full-featured implementation of the powerful Smalltalk programming language and environment.
When Smalltalk was created more than 35 years ago it defined the term object orientation and is the first language in which everything is built from objects. Smalltalk is deeply inspired by ideas from especially Simula, Sketchpad and Lisp and even today Smalltalk sets the bar for object oriented dynamically strongly typed interactive languages and environments.
You may be familiar with other open source languages like Ruby or Python, but Squeak takes these concepts much, much further offering a true uniform fully reflective environment, where everything is a real live object.
You will need four files: a Virtual Machine, a sources file, and image/changes file pair (provided by me for this class)
For more information, see the Squeak website.
Squeak Virtual Machine Download
If you are using a computer in the CS lab at PSU, the Squeak VM should already be installed.
If not, download it here: Unix (including MacOS X), Windows and others
Put this whereever your OS likes you to put executables.
Make a working directory for yourself
You will need the "sources" file. This a binary file, and is the same on all platforms. It is gzipped to discourage your download agent from treatiung it as a text file. Without this file, Squeak will complain that it can't find the sources, and you won't be able to browse the source code of the standard system classes. Unzip this file and put it in your working directory.
If, after a while, you have several working directories, you may find that you need several copies of the sources file. To avoid this, you can use symbolic or hard links instead of copies (However, on MacOS you can't use aliases). Alternatively, you can put the sources file in the same directory as the executable file that contains the Squeak VM. (On MacOs, that's inside the package/Contents/MacOS directory of the VM).
PSU Class image
Try it Out
Launch Squeak! Depeinding on your User Interface, double-click on the image file, drag the image file into the VM, or change to your working direcvtory and type <path to VM> <image file>.
Directory of more Squeak stuff
Resources for Learning Squeak
If you havn't used Squeak before, start with this tutorial, in particular Worksheet 1A. Also check out these (mostly free, downloadable) books.