Struct VariantMetadataHeader

pub(crate) struct VariantMetadataHeader {
    version: u8,
    is_sorted: bool,
    offset_size: OffsetSizeBytes,
}

Header structure for VariantMetadata

Fields

version: u8

is_sorted: bool

offset_size: OffsetSizeBytes

Note: This is offset_size_minus_one + 1

Implementations

impl VariantMetadataHeader

const fn offset_size(&self) -> u32

const fn first_offset_byte(&self) -> u32

pub(crate) fn try_new(header_byte: u8) -> Result<Self, ArrowError>

Tries to construct the variant metadata header, which has the form

             7     6  5   4  3             0
            +-------+---+---+---------------+
header      |       |   |   |    version    |
            +-------+---+---+---------------+
                ^         ^
                |         +-- sorted_strings
                +-- offset_size_minus_one

The version is a 4-bit value that must always contain the value 1.

• sorted_strings is a 1-bit value indicating whether dictionary strings are sorted and unique.
• offset_size_minus_one is a 2-bit value providing the number of bytes per dictionary size and offset field.
• The actual number of bytes, offset_size, is offset_size_minus_one + 1

Trait Implementations

impl Clone for VariantMetadataHeader

fn clone(&self) -> VariantMetadataHeader

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for VariantMetadataHeader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for VariantMetadataHeader

fn eq(&self, other: &VariantMetadataHeader) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for VariantMetadataHeader

impl StructuralPartialEq for VariantMetadataHeader