LogicalVar.java 

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package blog;

import java.util.*;
A logical variable. Specifically, a single LogicalVar object is used for the introduction of a logical variable in a particular scope, and for all uses of the variable in that scope. Unlike other terms, LogicalVar objects can be compared safely using ==.

Note that some LogicalVar objects are not created directly by the parser, but are returned by the getTermInScope method on SymbolTerm. This is because, in some contexts, the parser cannot distinguish a logical variable from a constant symbol based on local syntax alone. 


public class LogicalVar extends Term {
Creates a new LogicalVar with the given name and type. 


    public LogicalVar(String name, Type type) {
	this.name = name;
	this.type = type;
    }
Returns the name of this variable. 


    public String getName() {
	return name;
    }

    public boolean checkTypesAndScope(Model model, Map scope) {
	if (scope.get(name) != this) {
	    System.err.println(getLocation() + ": LogicalVar " + name  
			       + " is not in scope.");
	    return false;
	}
	return true;
    }
	
    public int compile(LinkedHashSet callStack) {
	return 0; // no compilation necessary for logical variables
    }
Returns the type of this variable. 


    public Type getType() {
	return type;
    }

    public Object evaluate(EvalContext context) {
	return context.getLogicalVarValue(this);
    }

    public BayesNetVar getVariable() {
	return new DerivedVar(this);
    }

    public boolean containsRandomSymbol() {
	return false;
    }

    public Set getFreeVars() {
	return Collections.singleton(this);
    }

    public ArgSpec getSubstResult(Substitution subst, 
				  Set<LogicalVar> boundVars) {
	if (boundVars.contains(this)) {
	    return this;
	}
	return subst.getReplacement(this);
    }

    public boolean makeOverlapSubst(Term t, Substitution theta){
	boolean ret =  theta.makeEqual(this,t);
	return ret;
    }

    public Term getCanonicalVersion() {
	return this; // can't canonicalize because this is a free variable
    }

    public LogicalVar makeNew() {
	return LogicalVar.createVar(type);
    }
Returns the name of this variable. 


    public String toString() {
	return name;
    }

    public static LogicalVar createVar(Type type) {
	counter++;
	return new LogicalVar("$" + counter, type);
    }

    private String name;
    private Type type;

    private static int counter = 0;
}

This file was generated on Tue Jun 08 17:53:36 PDT 2010 from file LogicalVar.java
by the ilog.language.tools.Hilite Java tool written by Hassan Aït-Kaci