Trait VTable

Source

pub trait VTable:
    'static
    + Clone
    + Sized
    + Send
    + Sync
    + Debug {
    type Array: 'static + Send + Sync + Clone + Debug + Deref<Target = dyn DynArray> + IntoArray;
    type Metadata: Debug;
    type OperationsVTable: OperationsVTable<Self>;
    type ValidityVTable: ValidityVTable<Self>;

Show 23 methods    // Required methods
    fn vtable(array: &Self::Array) -> &Self;
    fn id(&self) -> ArrayId;
    fn len(array: &Self::Array) -> usize;
    fn dtype(array: &Self::Array) -> &DType;
    fn stats(array: &Self::Array) -> StatsSetRef<'_>;
    fn array_hash<H: Hasher>(
        array: &Self::Array,
        state: &mut H,
        precision: Precision,
    );
    fn array_eq(
        array: &Self::Array,
        other: &Self::Array,
        precision: Precision,
    ) -> bool;
    fn nbuffers(array: &Self::Array) -> usize;
    fn buffer(array: &Self::Array, idx: usize) -> BufferHandle;
    fn buffer_name(array: &Self::Array, idx: usize) -> Option<String>;
    fn nchildren(array: &Self::Array) -> usize;
    fn child(array: &Self::Array, idx: usize) -> ArrayRef;
    fn child_name(array: &Self::Array, idx: usize) -> String;
    fn metadata(array: &Self::Array) -> VortexResult<Self::Metadata>;
    fn serialize(metadata: Self::Metadata) -> VortexResult<Option<Vec<u8>>>;
    fn deserialize(
        bytes: &[u8],
        _dtype: &DType,
        _len: usize,
        _buffers: &[BufferHandle],
        _session: &VortexSession,
    ) -> VortexResult<Self::Metadata>;
    fn build(
        dtype: &DType,
        len: usize,
        metadata: &Self::Metadata,
        buffers: &[BufferHandle],
        children: &dyn ArrayChildren,
    ) -> VortexResult<Self::Array>;
    fn with_children(
        array: &mut Self::Array,
        children: Vec<ArrayRef>,
    ) -> VortexResult<()>;
    fn execute(
        array: Arc<Array<Self>>,
        ctx: &mut ExecutionCtx,
    ) -> VortexResult<ExecutionResult>;

    // Provided methods
    fn append_to_builder(
        array: &Self::Array,
        builder: &mut dyn ArrayBuilder,
        ctx: &mut ExecutionCtx,
    ) -> VortexResult<()> { ... }
    fn execute_parent(
        array: &Array<Self>,
        parent: &ArrayRef,
        child_idx: usize,
        ctx: &mut ExecutionCtx,
    ) -> VortexResult<Option<ArrayRef>> { ... }
    fn reduce(array: &Array<Self>) -> VortexResult<Option<ArrayRef>> { ... }
    fn reduce_parent(
        array: &Array<Self>,
        parent: &ArrayRef,
        child_idx: usize,
    ) -> VortexResult<Option<ArrayRef>> { ... }
}

Expand description

The array VTable encapsulates logic for an Array type within Vortex.

The logic is split across several “VTable” traits to enable easier code organization than simply lumping everything into a single trait.

From this VTable trait, we derive implementations for the sealed DynArray and DynVTable traits.

The functions defined in these vtable traits will typically document their pre- and post-conditions. The pre-conditions are validated inside the DynArray and DynVTable implementations so do not need to be checked in the vtable implementations (for example, index out of bounds). Post-conditions are validated after invocation of the vtable function and will panic if violated.