public void toString(UnitPrinter up) {
up.startValueBox(this);
value.toString(up);
up.endValueBox(this);
}
public void setValue(Value value) {
if (canContainValue(value)) this.value = value;
else
throw new RuntimeException(
"Box " + this + " cannot contain value: " + value + "(" + value.getClass() + ")");
}