Explain the concept of difference between dynamic and static predicates in Prolog.
In Prolog, dynamic and static predicates are two different ways to define predicates and their behavior within a program. Here's an explanation of the concept and the difference between dynamic and static predicates:
1. Dynamic Predicates : * Dynamic predicates are defined using the `dynamic/1` directive in Prolog. * A dynamic predicate can have its clauses modified or extended dynamically during program execution. * Clauses of dynamic predicates can be added or removed at runtime using predicates like `assertz/1`, `retract/1`, and others. * Dynamic predicates are useful when you need to modify or update the definition of a predicate during program execution, such as adding new facts or rules dynamically. * Dynamic predicates provide flexibility and allow for the manipulation of program behavior at runtime.
2. Static Predicates : * Static predicates are the default in Prolog and do not require any special declaration or directive. * Once a static predicate is defined, its clauses cannot be modified or extended during program execution. * The clauses of static predicates are fixed and defined statically within the program. * Static predicates are typically used for representing fixed knowledge, facts, and rules that remain unchanged throughout the execution of the program. * Static predicates provide stability and predictability as their clauses cannot be modified dynamically.