Method new

src/metadata/schema.rs:87–111

Constructor for MetadataField Also checks that all FieldValue's are of the same variant

(name: String, values: HashSet<FieldValue>)

    ///
    /// Also checks that all FieldValue's are of the same variant
    pub fn new(name: String, values: HashSet<FieldValue>) -> Result<Self, Error> {
        // validate input
        let unique_types = values
            .iter()
            .map(|value| value.type_as_str())
            .collect::<HashSet<&str>>();
        if unique_types.len() > 1 {
            return Err(Error::InvalidFieldValues(
                "Field values must be homogeneous in type".to_owned(),
            ));
        }
        let value_index = set_to_value_index(values);
        let cardinality = value_index.len();
        // @NOTE: No. of dimensions are calculated to support 1 value
        // more than the cardinality because the index in value_index
        // starts with 1 and not 0. In other words, 0 is not used to
        // represent any value.
        let num_dims = nearest_power_of_two((cardinality + 1) as u16)
            .ok_or(Error::InvalidFieldCardinality(format!("Field = {name}")))?;
        Ok(Self {
            name,
            value_index,
            num_dims,
        })
    }

    /// Returns a numeric identifier for the value from the `value_index`
    pub fn value_id(&self, value: &FieldValue) -> Result<u16, Error> {