Trait narrow::Length

pub trait Length {
    // Required method
    fn len(&self) -> usize;

    // Provided method
    fn is_empty(&self) -> bool { ... }
}

The length (or number of elements) of a collection.

Required Methods

fn len(&self) -> usize

Returns the number of elements in the collection, also referred to as its length.

Provided Methods

fn is_empty(&self) -> bool

Returns true if there are no elements in the collection.

Implementations on Foreign Types

impl Length for &str

fn len(&self) -> usize

impl Length for String

fn len(&self) -> usize

impl Length for BooleanBuffer

Available on crate feature arrow-rs only.

fn len(&self) -> usize

impl Length for NullBuffer

Available on crate feature arrow-rs only.

fn len(&self) -> usize

impl<OffsetItem: OffsetElement> Length for OffsetBuffer<OffsetItem>

Available on crate feature arrow-rs only.

fn len(&self) -> usize

impl<T> Length for &[T]

fn len(&self) -> usize

impl<T> Length for &mut [T]

fn len(&self) -> usize

impl<T> Length for [T]

fn len(&self) -> usize

impl<T> Length for Box<[T]>

fn len(&self) -> usize

impl<T> Length for VecDeque<T>

fn len(&self) -> usize

impl<T> Length for Rc<[T]>

fn len(&self) -> usize

impl<T> Length for Arc<[T]>

fn len(&self) -> usize

impl<T> Length for Vec<T>

fn len(&self) -> usize

impl<T: FixedSize> Length for ScalarBuffer<T>

Available on crate feature arrow-rs only.

fn len(&self) -> usize

impl<T: FixedSize> Length for BufferBuilder<T>

Available on crate feature arrow-rs only.

fn len(&self) -> usize

impl<T: Length> Length for Option<T>

fn len(&self) -> usize

impl<const N: usize, T> Length for [T; N]

fn len(&self) -> usize

Implementors

impl<'a, T, const NULLABLE: bool, OffsetItem: OffsetElement, Buffer: BufferType> Length for OffsetSlice<'a, T, NULLABLE, OffsetItem, Buffer>

where <Buffer as BufferType>::Buffer<OffsetItem>: Validity<NULLABLE>,

impl<Buffer: BufferType> Length for Bitmap<Buffer>

impl<T, OffsetItem: OffsetElement, Buffer: BufferType> Length for Offset<T, false, OffsetItem, Buffer>

impl<T, OffsetItem: OffsetElement, Buffer: BufferType> Length for Offset<T, true, OffsetItem, Buffer>

impl<T: Array, const NULLABLE: bool, OffsetItem: OffsetElement, Buffer: BufferType> Length for VariableSizeListArray<T, NULLABLE, OffsetItem, Buffer>

where <Buffer as BufferType>::Buffer<OffsetItem>: Validity<NULLABLE>, Offset<T, NULLABLE, OffsetItem, Buffer>: Length,

impl<T: StructArrayType, const NULLABLE: bool, Buffer: BufferType> Length for StructArray<T, NULLABLE, Buffer>

where <T as StructArrayType>::Array<Buffer>: Validity<NULLABLE>, <<T as StructArrayType>::Array<Buffer> as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<T: Unit> Length for Nulls<T>

impl<T: Unit, const NULLABLE: bool, Buffer: BufferType> Length for NullArray<T, NULLABLE, Buffer>

where Nulls<T>: Validity<NULLABLE>, <Nulls<T> as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<T: LogicalArrayType, const NULLABLE: bool, Buffer: BufferType, OffsetItem: OffsetElement, UnionLayout: UnionType> Length for LogicalArray<T, NULLABLE, Buffer, OffsetItem, UnionLayout>

where <T as LogicalArrayType>::Array<Buffer, OffsetItem, UnionLayout>: Validity<NULLABLE>, <<T as LogicalArrayType>::Array<Buffer, OffsetItem, UnionLayout> as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<T: FixedSize, const NULLABLE: bool, Buffer: BufferType> Length for FixedSizePrimitiveArray<T, NULLABLE, Buffer>

where <Buffer as BufferType>::Buffer<T>: Validity<NULLABLE>, <<Buffer as BufferType>::Buffer<T> as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<const N: usize, T, const NULLABLE: bool, Buffer: BufferType> Length for FixedSizeListArray<N, T, NULLABLE, Buffer>

where T: Validity<NULLABLE> + Array, <T as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<const NULLABLE: bool, Buffer: BufferType> Length for BooleanArray<NULLABLE, Buffer>

where Bitmap<Buffer>: Validity<NULLABLE>, <Bitmap<Buffer> as Validity<NULLABLE>>::Storage<Buffer>: Length,

impl<const NULLABLE: bool, OffsetItem: OffsetElement, Buffer: BufferType> Length for StringArray<NULLABLE, OffsetItem, Buffer>

where <Buffer as BufferType>::Buffer<OffsetItem>: Validity<NULLABLE>, VariableSizeBinaryArray<NULLABLE, OffsetItem, Buffer>: Length,

impl<const NULLABLE: bool, OffsetItem: OffsetElement, Buffer: BufferType> Length for VariableSizeBinaryArray<NULLABLE, OffsetItem, Buffer>

where <Buffer as BufferType>::Buffer<OffsetItem>: Validity<NULLABLE>, Offset<FixedSizePrimitiveArray<u8, false, Buffer>, NULLABLE, OffsetItem, Buffer>: Length,