In the last century, sometimes I was studying Squeak. Now, in these days I have returned to visit it, and wanted to write a simple, introductory article, on its easy installation.
Squeak is an open source implementation of Smalltalk, that has been developed for years. The internal implementation of its virtual machine is interesting, to a great extent written in Smalltalk, with tools to produce its own virtual machine.
Like in other implementations, one needs to install the virtual machine of the operating system that will use. In this article, we will install a version (the 3,9) for Windows. Also we will need an image, a file with the state of the active instances. Smalltalk has been characterized from always, by being able to write and to raise an image, a species of “snapshot” of the state of the system.
The page of Squeak is
For somebody not warned of the existence of virtual machines and images, it is a little confused explanation of its installation:
because there are several options. For example, to lower the versions from
But there is multitude of archives. The one that we are going to use is a file .zip that contains the virtual machine for Windows and image 3,9 (at the moment already there is a developing image 3,10), directly from:
This file contains:
We see a Squeak.exe, that it is the feasible virtual machine. The SqueakV39.sources file is of text, of more than 4 megas of size. It contains the source code of the classes that compose this version. The file Squeak3.9-end-7067.image is the image, “snapshot” that contains the instances of this system.
We can expand the content of this .zip in a directory, and make double click on the feasible one of the virtual machine Squeak.exe. Automatically it detects the image. Alternatively, we could drag from the Explorer de Windows the file image on the file .exe. It appears our first welcome to the Squeak world:
All within this window, is created by the own Squeak. Following the tradition of the original Smalltalk, the graphical aspect, the controls, windows, and others “widgets” are drawn by the own system. The appearance of this window and its contents, then, is independent of the operating system.
In the right lapel titled tools, we found a series of tools. Raising the classic one “to browser” of Smalltalk, we found:
The four superior lists, show, in sequence:
categories of classes
classes of the selected category
categories of methods (of instance or class)
In the screen capture it appears the classic Object, of Kernel-Objects.
If you have interest on the virtual machine, can visit
He is interesting to see the instructions to produce a virtual machine, in Win32:
Well, for today, enough. I hope that it serves to you, as an start in the use of this implementation of Smalltalk.
Angel “Java” Lopez