Safe Dynamic Multiple Inheritance

Resumé

Combination of descriptive entities--i.e. multiple inheritance and related mechanisms--is usually only supported at compile time in statically typed languages. The language gbeta is statically typed and has supported run-time creation of classes and methods since 1997, by means of the pattern combination operator '&'. However, with certain combinations of operands the '&' operator fails; as a result, creation of new classes and methods at run-time had to be considered a dangerous operation. This paper presents a large and useful class of combinations, and proves that combinations in this class will always succeed.