com.svincent.moksa
Class PrologEngine

java.lang.Object
  |
  +--com.svincent.moksa.WamObject
        |
        +--com.svincent.moksa.PrologEngine

public class PrologEngine

extends WamObject

Global context for everything, plus a public interface for users.

Inner Class Summary

class	PrologEngine.AddHandler
static class	PrologEngine.ArithmeticHandler
class	PrologEngine.NegateHandler
class	PrologEngine.SubtractHandler

Field Summary

boolean	debug
boolean	debugUnify
boolean	trace Debug flags inlined for speed and comfort.

Constructor Summary

PrologEngine()
Make a new PrologEngine.

Method Summary

void	addArithmeticHandler(PrologEngine.ArithmeticHandler ah)
void	asserta(PrologTerm term) Asserts a new clause before all clauses of the definition of the given predicate.
void	asserta(Rule rule) Asserts a new clause before all clauses of the definition of the given predicate.
void	assertz(PrologTerm term) Asserts a new clause after all clauses of the definition of the given predicate.
void	assertz(Rule rule) Asserts a new clause after all clauses of the definition of the given predicate.
Rule	compileRule(PrologTerm term)
PrologFactory	getFactory() Retrieve the new object Factory used in this PrologEngine.
void	installArithmeticHandlers()
void	installBuiltins() Install all the builtin rules.
boolean	invoke(CompoundTerm goal) Utility method from outside.
void	loadModule(java.lang.String moduleName)
IndentPrintWriter	log() Retrieve the current output log.
PrologEngine.ArithmeticHandler	lookupArithmeticHandler(java.lang.String name)
Variable[]	solve(CompoundTerm goal) Utility method from outside.

Methods inherited from class com.svincent.moksa.WamObject

tag, tag

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

trace

public boolean trace

Debug flags inlined for speed and comfort.

debug

public boolean debug

debugUnify

public boolean debugUnify

Constructor Detail

PrologEngine

public PrologEngine()

Make a new PrologEngine.

Method Detail

getFactory

public PrologFactory getFactory()

Retrieve the new object Factory used in this PrologEngine.

log

public IndentPrintWriter log()

Retrieve the current output log.

asserta

public void asserta(PrologTerm term)
             throws PrologException

Asserts a new clause before all clauses of the definition of the given predicate.

assertz

public void assertz(PrologTerm term)
             throws PrologException

Asserts a new clause after all clauses of the definition of the given predicate.

asserta

public void asserta(Rule rule)

Asserts a new clause before all clauses of the definition of the given predicate.

assertz

public void assertz(Rule rule)

Asserts a new clause after all clauses of the definition of the given predicate.

solve

public Variable[] solve(CompoundTerm goal)
                 throws PrologException

Utility method from outside. solves 'goal':

• On success, returns array of bound variables from goal
• On failure, returns null

invoke

public boolean invoke(CompoundTerm goal)
               throws PrologException

Utility method from outside. solves 'goal':

• On success, returns true
• On failure, returns false

installBuiltins

public void installBuiltins()

Install all the builtin rules.

There are big issues with this, particularly w.r.t. memory consumption. Rather, I should load things dynamically (maybe have a lookup table of modules that can be loaded by function name or something...)

XXX when we do modules, there can be a dynamic module called 'java', which allows builtin classes to be dynamically loaded. Much nicer.

installArithmeticHandlers

public void installArithmeticHandlers()

addArithmeticHandler

public void addArithmeticHandler(PrologEngine.ArithmeticHandler ah)

lookupArithmeticHandler

public PrologEngine.ArithmeticHandler lookupArithmeticHandler(java.lang.String name)

compileRule

public Rule compileRule(PrologTerm term)
                 throws PrologException

loadModule

public void loadModule(java.lang.String moduleName)
                throws PrologException