toolbus.process
Class Iteration

java.lang.Object
  toolbus.process.ProcessExpression
      toolbus.process.Iteration

public class Iteration
extends ProcessExpression

Iteration implements the process expression P1 * P2. The current implementation does not handle the following case correctly: if Test1 then P1 * if Test2 then A . B . C fi else ... fi Problem: Test1 will be attached to A, but the first iteration of P1 may have modified local variables in such a way that Test1 has become false. We solve this in TscriptParser by prefixing every iteration with an extra tau so the test is always executed in an unmodified environment. So the above example becomes: if Test1 then tau. P1 * if Test2 then A . B . C fi else ... fi and Test1 will be attached to tau (and is guaranteed to be still true when this branch is taken).

Field Summary

private ProcessExpression	left
private ProcessExpression	right

Fields inherited from class toolbus.process.ProcessExpression

posInfo, tbfactory

Constructor Summary

Iteration(ProcessExpression left, ProcessExpression right, TBTermFactory tbfactory, PositionInformation posInfo)

Method Summary

protected void	compile(ProcessInstance P, java.util.Stack<java.lang.String> calls, State follow)
protected void	computeFirst()
protected ProcessExpression	copy()
AtomList	getAtoms()
protected void	replaceFormals(Environment env)
java.lang.String	toString()

Methods inherited from class toolbus.process.ProcessExpression

addToFirst, addToFollow, getFirst, getFollow, getPosInfo, setFirst, setFollow

Methods inherited from class java.lang.Object

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

Field Detail

left

private final ProcessExpression left

right

private final ProcessExpression right

Constructor Detail

Iteration

public Iteration(ProcessExpression left,
                 ProcessExpression right,
                 TBTermFactory tbfactory,
                 PositionInformation posInfo)

Method Detail

copy

protected ProcessExpression copy()

Specified by:

copy in class ProcessExpression

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

computeFirst

protected void computeFirst()

Specified by:

computeFirst in class ProcessExpression

compile

protected void compile(ProcessInstance P,
                       java.util.Stack<java.lang.String> calls,
                       State follow)
                throws ToolBusException

Specified by:

compile in class ProcessExpression

Throws:

ToolBusException

replaceFormals

protected void replaceFormals(Environment env)
                       throws ToolBusException

Specified by:

replaceFormals in class ProcessExpression

Throws:

ToolBusException

getAtoms

public AtomList getAtoms()

Specified by:

getAtoms in class ProcessExpression