Database class final

An indexed collection of Prolog Rule definitions that can be queried.

Rules are indexed by head functor name for fast candidate lookup during goal resolution.

For example:

final db = Database.parse('parent(tom, bob). parent(bob, ann).');
final goal = Term.parse('parent(tom, X)');
for (final result in db.query(goal)) {
  print(result); // parent(tom, bob)
}

Annotations

• @immutable

Constructors

Database(Iterable<Rule> rules)

Creates a database populated with rules.

Database.parse(String rules)

Parses a string of Prolog rules into a Database.

factory

Properties

hashCode → int

The hash code for this object.

no setter, inherited

rules → Map<String, List<Rule>>

Map of rule head functor names to candidate rules.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

query(Term goal) → Iterable<Node>

Queries the database with goal, yielding unified solution terms.

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited