Sigma Calculus Interpreter, by Santiago M. Pericas-Geertsen

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A distributed language based on the imperative object calculus

The core of the Obliq language is essentially the imperative object calculus of Chapter 10. You can run the examples given there in Obliq, with very superficial changes. Moreover, you can run most examples from the "functional" chapters in Obliq by adding a cloning operation before every update.