AweSOM - The Simple Object Machine Smalltalk implemented in Smalltalk

Introduction

SOM is a minimal Smalltalk dialect used to teach VM construction at the Hasso Plattner Institute. It was originally built at the University of Århus (Denmark) where it was used for teaching and as the foundation for Resilient Smalltalk.

This repository contains the Smalltalk-based implementation of SOM, including SOM's standard library and a number of examples. In addition to AweSOM, other implementations exist for Java (SOM), C (CSOM), C++ (SOM++), and Python (PySOM). Please see the main project page for links to other VM implementations.

A simple Hello World looks like:

Hello = (
  run = (
    'Hello World!' println.
  )
)

This particular repository represents a fork of AweSOM, which was ported to Cuis Smalltalk.

Setup

Install the core-lib submodule, which downloads the core library of SOM, written in SOM. Which in turn is used by the Cuis implementation inside the image for core libraries and testcases.

git submodule update --init

Then install the packages contained in the repository in an image and place the resulting image into the repository directory. This needs to be done, so that the testcases and any SOM code can see the core-lib.

For installing the packages do:

Feature require: 'AweSOM-Meta'.
Feature require: 'AweSOM-Test'.
Feature require: 'AweSOM-Compiler'.
Feature require: 'AweSOM-CoreObjects'.
Feature require: 'AweSOM-Interpreter'.
Feature require: 'AweSOM-VM'.

Playing around

For printing "Hello World" on the transcript do-it in a Workspace:

universe := SOMUniverse new.
universe setupDefaultClasspath.

universe eval: '''Hello World'' println'.

AweSOM is a little bit "goatish" when it comes to searching the class path. When a "message not found" error occurs on the UndefinedObject, then it's very likely that the system didn't find the core-lib class-path, there it needs to read from the Smalltalk directory the base classes. When it doesn't find them it ignores them silently and now the whole base system is not defined.

Another way of running a Hello World example is to create the class and then run it. This is what #eval: does indirectly.

To do that by hand do-it the following in a Workspace:

universe := SOMUniverse new.
universe setupDefaultClasspath.

universe loadAndStoreFromSource: 'Hello = (
  run = (
    ''Hello World!'' println.
  )
)'.

universe start: {'Hello'}.

Which will print too in an open Transcript "Hello World".

Links