Lazy Evaluation and Nondeterminism make Backus\u27 FP-systems More Practical

Backus\u27 FP-systems are made more practical by introducing into them lazy evaluation and nondeterminism. This is done in the framework of a concrete programming language called FP*. From the one hand, this language is almost as mathematical as FP-systems are. From the other hand, it gives the possibility to manage secondary memory and to develop such applications as, for instance, interactive and distributed file systems. Experimental versions of a compiler and an interpreter for the FP* language are implemented