@Override
    public Value add(Value value) {
        if (value instanceof TensorValue tensor)
            return tensor.add(this);
        else
            return new DoubleValue(asDouble() + value.asDouble());
    }
A value which acts as a double in numerical context.

@author bratseth
searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleCompatibleValue.java