} else {           for (int i = 0; i < prefixNumSlots; ++i) { if (prevVnaFrame.getValue(i).equals(replaceMe)) { ValueNumber corresponding = targetVnaFrame.getValue(i); for (int j = 0; j < targetNumSlots; ++j) { if (targetVnaFrame.getValue(j).equals(corresponding)) frame.setValue(j, replacementValue); } } } }
	private IsNullValueFrame replaceValues(IsNullValueFrame origFrame, IsNullValueFrame frame,		ValueNumber replaceMe, ValueNumberFrame vnaFrame, IsNullValue replacementValue) {		// If required, make a copy of the frame		frame = modifyFrame(origFrame, frame);		// The VNA frame may have more slots than the IsNullValueFrame		// if it was produced by an IF comparison (whose operand or operands		// are subsequently popped off the stack).		final int numSlots = Math.min(frame.getNumSlots(), vnaFrame.getNumSlots());		for (int i = 0; i < numSlots; ++i) {			if (vnaFrame.getValue(i).equals(replaceMe))				frame.setValue(i, replacementValue);		}		return frame;	}