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Class prolog.Goal

java.lang.Object
   |
   +----prolog.Goal

public abstract class Goal

extends Object

implements Cloneable, Serializable

Goal()

compile(ClauseCodeGen)

instantiate(Term[])

Instantiate a list of Goals with the given substitutions.

normalise(Variable[], int, Vector, TypeDictionary)

Copies and normalises the body of a predicate.

redo(Term[], Prolog, ChoicePoint)

toString()

unify(Term[], Prolog)

 Goal()

 public abstract boolean unify(Term insts[],
                               Prolog p) throws PrologException

 public abstract boolean redo(Term insts[],
                              Prolog p,
                              ChoicePoint cp) throws PrologException

 abstract void instantiate(Term insts[])

Instantiate a list of Goals with the given substitutions. We overwrite the old Compound objects in the tree with their instantiated counterparts.

 abstract Goal normalise(Variable vars[],
                         int next_free_var,
                         Vector new_vars,
                         TypeDictionary types)

Copies and normalises the body of a predicate.

The body consists of unify()'s and calls to other predicates. Ensure the following conditions hold:

 1. All unifications have the form: unify(X, S).
      where: X is a variable
             S is one of: variable
                          number
                          structure containing new variables.
 2. Calls contain variables only.
 

See Also:

normalise

 boolean compile(ClauseCodeGen ccg)

Parameters:

side_effects - have any calls up to now caused side effects?

 public abstract String toString()

Overrides:

toString in class Object

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