GNU Prolog for Java

gnu.prolog.vm.interpreter.instruction
Class IDup

java.lang.Object
  extended by gnu.prolog.vm.interpreter.instruction.Instruction
      extended by gnu.prolog.vm.interpreter.instruction.IDup
All Implemented Interfaces:
Installable

public class IDup
extends Instruction

duplicate top of pushdown stack


Field Summary
 
Fields inherited from class gnu.prolog.vm.interpreter.instruction.Instruction
codePosition
 
Constructor Summary
IDup()
           
 
Method Summary
 int execute(ExecutionState state, BacktrackInfo bi)
          execute call instruction within specified sate
 String toString()
          convert instruction to string
 
Methods inherited from class gnu.prolog.vm.interpreter.instruction.Instruction
install, uninstall
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

IDup

public IDup()
Method Detail

execute

public int execute(ExecutionState state,
                   BacktrackInfo bi)
            throws PrologException
execute call instruction within specified sate

Specified by:
execute in class Instruction
Parameters:
state - state within which instruction will be executed
Returns:
instruction to caller how to execute next instruction
Throws:
PrologException - if code is throwing prolog exception

toString

public String toString()
convert instruction to string

Overrides:
toString in class Object

GNU Prolog for Java