The study of self-replicating structures in Computer Science has been taking place for more than half a century, motivated by the desire to understand the fundamental principles and algorithms involved in self-replication. The bulk of the literature explores self-replicating forms in Cellular Automata. Though trivially self-replicating programs have been written for dozens of languages, very little work exists that explores self-replicating forms in programming languages. This paper reports initial investigations into self- replicating expressions in the Lambda Calculus, the basis for functional programming languages. Mimicking results from the work on Cellular Automata, self- replicating Lambda Calculus expressions that also allow the application of an arbitrary program to arbitrary data are presented. Standard normal order reduction, however, will not reduce the sub-expression representing the program application. Two approaches of dealing with this, hybrid reduction and parallel reduction, are discussed, and have been im- plemented in an interpreter. |
(from crpit.com)
