Trait ExtVTable 

pub trait ExtVTable:
    Sized
    + 'static
    + Send
    + Sync
    + Clone
    + Debug
    + Eq
    + Hash {
    type Metadata: 'static + Send + Sync + Clone + Debug + Display + Eq + Hash;
    type NativeValue<'a>: Display;

    // Required methods
    fn id(&self) -> Id;
    fn serialize_metadata(
        &self,
        metadata: &Self::Metadata,
    ) -> Result<Vec<u8>, VortexError>;
    fn deserialize_metadata(
        &self,
        metadata: &[u8],
    ) -> Result<Self::Metadata, VortexError>;
    fn validate_dtype(ext_dtype: &ExtDType<Self>) -> Result<(), VortexError>;
    fn unpack_native<'a>(
        ext_dtype: &'a ExtDType<Self>,
        storage_value: &'a ScalarValue,
    ) -> Result<Self::NativeValue<'a>, VortexError>;

    // Provided methods
    fn can_coerce_from(ext_dtype: &ExtDType<Self>, other: &DType) -> bool { ... }
    fn can_coerce_to(ext_dtype: &ExtDType<Self>, other: &DType) -> bool { ... }
    fn least_supertype(
        ext_dtype: &ExtDType<Self>,
        other: &DType,
    ) -> Option<DType> { ... }
    fn validate_scalar_value(
        ext_dtype: &ExtDType<Self>,
        storage_value: &ScalarValue,
    ) -> Result<(), VortexError> { ... }
}

The public API for defining new extension types.

This is the non-object-safe trait that plugin authors implement to define a new extension type. It specifies the type’s identity, metadata, serialization, and validation.

Required Associated Types

type Metadata: 'static + Send + Sync + Clone + Debug + Display + Eq + Hash

Associated type containing the deserialized metadata for this extension type.

type NativeValue<'a>: Display

A native Rust value that represents a scalar of the extension type.

The value only represents non-null values. We denote nullable values as Option<Value>.

Required Methods

fn id(&self) -> Id

Returns the ID for this extension type.

fn serialize_metadata( &self, metadata: &Self::Metadata, ) -> Result<Vec<u8>, VortexError>

Serialize the metadata into a byte vector.

fn deserialize_metadata( &self, metadata: &[u8], ) -> Result<Self::Metadata, VortexError>

Deserialize the metadata from a byte slice.

fn validate_dtype(ext_dtype: &ExtDType<Self>) -> Result<(), VortexError>

Validate that the given storage type is compatible with this extension type.

fn unpack_native<'a>( ext_dtype: &'a ExtDType<Self>, storage_value: &'a ScalarValue, ) -> Result<Self::NativeValue<'a>, VortexError>

Validate and unpack a native value from the storage ScalarValue.

Note that ExtVTable::validate_dtype() is always called first to validate the storage crate::dtype::DType, and the Scalar implementation will verify that the storage value is compatible with the storage dtype on construction.

Errors

Returns an error if the storage ScalarValue is not compatible with the extension type.

Provided Methods

fn can_coerce_from(ext_dtype: &ExtDType<Self>, other: &DType) -> bool

Can a value of other be implicitly widened into this type? (e.g. GeographyType might accept Point, LineString, etc.)

Implementors only need to override one of can_coerce_from or can_coerce_to. We have both so that either side of the coercion can provide the logic.

fn can_coerce_to(ext_dtype: &ExtDType<Self>, other: &DType) -> bool

Can this type be implicitly widened into other?

Implementors only need to override one of can_coerce_from or can_coerce_to. We have both so that either side of the coercion can provide the logic.

fn least_supertype(ext_dtype: &ExtDType<Self>, other: &DType) -> Option<DType>

Given two types in a Uniform context, what is their least supertype?

Return None if no supertype exists.

fn validate_scalar_value( ext_dtype: &ExtDType<Self>, storage_value: &ScalarValue, ) -> Result<(), VortexError>

Validate the given storage value is compatible with the extension type.

By default, this calls unpack_native() and discards the result.

Errors

Returns an error if the storage ScalarValue is not compatible with the extension type.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl ExtVTable for FixedShapeTensor

type Metadata = FixedShapeTensorMetadata

type NativeValue<'a> = &'a ScalarValue

fn id(&self) -> Id

fn serialize_metadata( &self, metadata: &<FixedShapeTensor as ExtVTable>::Metadata, ) -> Result<Vec<u8>, VortexError>

fn deserialize_metadata( &self, metadata: &[u8], ) -> Result<<FixedShapeTensor as ExtVTable>::Metadata, VortexError>

fn least_supertype( ext_dtype: &ExtDType<FixedShapeTensor>, other: &DType, ) -> Option<DType>

fn validate_dtype( ext_dtype: &ExtDType<FixedShapeTensor>, ) -> Result<(), VortexError>

fn unpack_native<'a>( _ext_dtype: &'a ExtDType<FixedShapeTensor>, storage_value: &'a ScalarValue, ) -> Result<<FixedShapeTensor as ExtVTable>::NativeValue<'a>, VortexError>

impl ExtVTable for Vector

type Metadata = EmptyMetadata

type NativeValue<'a> = &'a ScalarValue

fn id(&self) -> Id

fn serialize_metadata( &self, _metadata: &<Vector as ExtVTable>::Metadata, ) -> Result<Vec<u8>, VortexError>

fn deserialize_metadata( &self, _metadata: &[u8], ) -> Result<<Vector as ExtVTable>::Metadata, VortexError>

fn least_supertype(ext_dtype: &ExtDType<Vector>, other: &DType) -> Option<DType>

fn validate_dtype(ext_dtype: &ExtDType<Vector>) -> Result<(), VortexError>

fn unpack_native<'a>( _ext_dtype: &'a ExtDType<Vector>, storage_value: &'a ScalarValue, ) -> Result<<Vector as ExtVTable>::NativeValue<'a>, VortexError>

Implementors

impl ExtVTable for Date

type Metadata = TimeUnit

type NativeValue<'a> = DateValue

impl ExtVTable for Time

type Metadata = TimeUnit

type NativeValue<'a> = TimeValue

impl ExtVTable for Timestamp

type Metadata = TimestampOptions

type NativeValue<'a> = TimestampValue<'a>

impl ExtVTable for Uuid

type Metadata = UuidMetadata

type NativeValue<'a> = Uuid