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Smalltalk Challenge: Post 2 - Switching to Squeak

A quick survey of Smalltalk's keywords, constructs, and syntax isn't enough to understand how the language approaches programming. There is only a handful of keywords, no control structures, and the syntax is quirky in spots but is hardly exotic. To really get an appreciation, it's helpful to place the language in its historical context. Smalltalk wasn't intended to be a general purpose systems programming language like C, rather it was designed to allow ordinary people to take full advantage of their computers and to be easy enough for children to learn. The intended environment was immersive, interactive, and most-importantly visual. Smalltalk was more than a programming language, it was an entire operating environment.

Xerox was working on the Dynabook at its Palo Alto Research Center in the early 1970's. The Dynabook was to have many features we now see in personal laptops and tablet devices (such as touch screens, mice, windowed display managers, etc.). Alan Kay argued that existing languages were ill-suited and a new programming language was necessary for the end-user to realize the full potential of the system. He drew inspiration from the work of Jean Piaget and others in developmental psychology and constructionist learning, which set the direction of Smalltalk. The Dynabook project never came to fruition, but Smalltalk lives on, and both had a lasting influence on computing that we still see today.

Given this background, I suspected something like Squeak would really be better suited for learning Smalltalk as it was intended since Squeak is the modern implementation of the language and environment that was developed at Palo Alto. I asked Josh if it was okay to switch from GNU Smalltalk to Squeak. He agreed-- admitting that he only proposed GNU Smalltalk because it's what he already had on his system from Portage. I checked apt and was amazed to find Squeak in Ubuntu's repositories (with bets on the MotU pulling it without telling anyone within the next two releases). After running sudo apt-get install squeak-vm and starting Squeak, I was staring at a pretty gaudy looking graphical environment.

I took the liberty of running a "Hello World" program. The System Browser window is at the top, a Workspace window is in the middle, the Transcript window is at the bottom, and the Objects Library window is to the right. I entered the statement Transcript show: 'Hello World!' in the Workspace, highlighted it, and chose "do it" from the popup menu.

Every element is an object which you interact with by sending it messages. In the above example for instance, I interacted with the Transcript window by sending it the show: message and the argument 'Hello World!'. The window responded by displaying the text.

I did a screen recording of another example to help give you a better idea what interaction in the graphical environment can look like. I placed a Star object on the world (the main "desktop" area) and used its Inspection window to send the messages borderWidth: and rotationDegrees:. The object responded by redrawing itself with a thicker border and different rotation.

Have you been challenged to learn a new language, or have you been learning/working with Smalltalk? Feel free to leave your comments about it below.

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