Oberon is a general-purpose programming language that evolved from Modula-2. Its principal new feature is the concept of type extension. It permits the construction of new data types on the basis of existing ones and to relate them.
This report is not intended as a programmer's tutorial. It is intentionally kept concise. Its function is to serve as a reference for programmers, implementors, and manual writers. What remains unsaid is mostly left so intentionally, either because it is derivable from stated rules of the language, or because it would unnecessarily restrict the freedom of implementors.
This document describes the language defined in 1988/90 as revised in 2007/11.»