CSE 360: Lecture 4

Examples of using various lambda Prolog modules

In class, we shall discuss the following three modules.

• Computation of paths in a graph given the adjacency information of that graph. The module path.mod contains the description of a particular graph and the program for computing its transitive closure. The file path.ses contains an example session using this code.

• The natural numbers 0, 1, 2, 3, .... are built into lambda Prolog, along with operations to compute on them. It is interesting to re-create a version of these numbers using terms, in the following correspondence

       0      z
       1      (s z)
       2      (s (s z))
       3      (s (s (s z)))
       4      (s (s (s (s z))))
       

  and so on. The module peano.mod contains the definition of this data structure and various predicates for computing on these numbers. The file peano.ses contains an example session using this code.

• Lists are a common data structure and the module lists.mod contains the description of some simple list programs. The file lists.ses contains an example session using this code.