SOM++ - The Simple Object Machine implemented in C++

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 also used for teaching.

Currently, implementations exist for Java (SOM), C (CSOM), C++ (SOM++), Python (PySOM), RPython (RPySOM), the Truffle framework (TruffleSOM), and Squeak/Pharo Smalltalk (AweSOM).

A simple SOM Hello World looks like:

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

This repository contains the C++ implementation of SOM, including an implementation of the SOM standard library and a number of examples. Please see the main project page for links to the VM implementations.

SOM++ uses CMake for building:

$ mkdir cmake-build && cd cmake-build
$ cmake ..
$ make

Afterwards, the tests can be executed with:

$ ./SOM++ -cp ../Smalltalk ../TestSuite/TestHarness.som

A simple Hello World program is executed with:

$ ./SOM++ -cp ../Smalltalk ../Examples/Hello.som

Note: On Linux, the library search path needs to be adapted:

$ export LD_LIBRARY_PATH=.

The debug version of CSOM can be built using the debug target:

$ make debug

Information on previous authors are included in the AUTHORS file. This code is distributed under the MIT License. Please see the LICENSE file for details. Additional documentation, detailing for instance the object model and how to implement primitives, is available in the doc folder.

Advanced Compilation Settings

SOM++ supports different garbage collectors, including a basic mark/sweep, and a generational GC. Furthermore, it implements different variants for integer handling.

Tagged integers:

default: off
option name: TAGGING
example: cmake .. -DUSE_TAGGING=true

Integer caching:

default: off
option name: INT_CACHE
example: cmake .. -DCACHE_INTEGER=true

Build Status

Thanks to GitHub Actions, all commits of this repository are tested. The current build status is: