assert ntimes == 1 : "Need code here to handle multiple pop";  JLocalVariableExpression ref = new JLocalVariableExpression( null, var);  return new SIRPeekExpression(new JPostfixExpression(null, OPE_POSTINC, ref), oldTapeType); }
                public Object visitPopExpression(SIRPopExpression oldSelf,                                                 CType oldTapeType) {                    // Recurse into children.                    SIRPopExpression self = (SIRPopExpression)                        super.visitPopExpression(oldSelf,                                                 oldTapeType);                    // reference our var                    JLocalVariableExpression ref = new JLocalVariableExpression(null,                                                                                var);                    // Return new peek expression.                    return new SIRPeekExpression(new JPostfixExpression(null,                                                                        OPE_POSTINC,                                                                        ref),                                                 oldTapeType);                }