Towards explicit inheritance schemes

Although the shared-information model on which inheritance schemes are based is clean and simple, inheritance implementations encountered in today´s object-oriented systems are usually a lot more complex. The author claims that this complexity mainly originates from a desire to express too many different concepts by means of one very tangled inheritance lattice. He argues in favor of simpler inheritance schemes, intelligible and without exceptions, that allow the user to build more complicated information-retrieval architectures explicitly when necessary. This contributes to the simplicity of the language and hence to the comfort of the programmer. Three different object-oriented languages are presented that each illustrate an alternative inheritance mechanism that fulfils these requirements.<>