Page 221 - DCAP506_ARTIFICIAL_INTELLIGENCE

Unit 14: Prolog

18. You should ...................... a current stream only if you desire to consequently use it frequently Notes
for input or output.

14.11 Summary

 Prolog is a logical and a declarative programming language. The name itself, Prolog, is
short for PROgramming in LOGic.
 In ProLog, facts describe the relationships between different objects and are independent
of each other.
 In ProLog, rules are used in the process of decision-making and can deduce new facts from
existing ones.

 Proposing a query means demanding Prolog to attempt to prove that the statement(s)
implied by the query can be prepared true given the right variable instantiations are
prepared.
 An atom is a general-purpose name with no inherent meaning. It is composed of a sequence
of characters that is parsed by the Prolog reader as a single unit.
 Variables are denoted by a string consisting of letters, numbers and underscore characters,
and beginning with an uppercase letter or underscore.

 A compound term is composed of an atom called a functor and a number of “arguments”,
which are again terms.
 The predicate repeat functions in the traditional manner, i.e., whenever backtracking
reaches it, execution continues forward again via the same clauses as if another substitute
had been found.

 Two terms are defined to match if they are either indistinguishable or if they can be made
indistinguishable by variable instantiation.
 The backtracking predicate provides an alternative path for a program when the current
path fails.

14.12 Keywords

Atom: An atom is a general-purpose name with no inherent meaning. It is composed of a
sequence of characters that is parsed by the Prolog reader as a single unit.
Backtracking: The backtracking predicate provides an alternative path for a program when the
current path fails.

Compound Term: A compound term is composed of an atom called a functor and a number of
"arguments", which are again terms.
Facts: In ProLog, facts describe the relationships between different objects and are independent
of each other.
Matching: Two terms are defined to match if they are either indistinguishable or if they can be
made indistinguishable by variable instantiation.

Prolog: Prolog is a logical and a declarative programming language. The name itself, Prolog, is
short for PROgramming in LOGic.
Repeat: The predicate repeat functions in the traditional manner, i.e., whenever backtracking
reaches it, execution continues forward again via the same clauses as if another substitute had
been found.

LOVELY PROFESSIONAL UNIVERSITY 215