private void parseDenseSubspace(TensorAddress mappedAddress, List<String> denseDimensionOrder) {
            var subBuilder = ((MixedTensor.BoundBuilder)builder).denseSubspaceBuilder(mappedAddress);
            var rest = string.substring(position);
            DenseValueParser denseParser = new DenseValueParser(rest,
                                                                denseDimensionOrder,
                                                                subBuilder);
            denseParser.parse();
            position += denseParser.position();
        }
Creates a tensor address from a string on the form {dimension1:label1,dimension2:label2,...}
vespajlib/src/main/java/com/yahoo/tensor/TensorParser.java