Struct OffsetsVector 

pub struct OffsetsVector { /* private fields */ }

Compact vector of offsets

Stores offsets using a compact representation.

Implementations

impl OffsetsVector

pub fn new() -> Self

Create a new empty offsets vector

pub fn push(&mut self, offset: u64)

Add an offset to the vector

pub fn access(&self, i: usize) -> u64

Get the offset at index i

pub fn decode(&self, absolute_offset: u64) -> DecodedOffset

Decode an offset (currently identity since we don’t compress yet)

pub fn len(&self) -> usize

Get the number of offsets

pub fn is_empty(&self) -> bool

Check if the vector is empty

pub fn num_bytes(&self) -> u64

Get the number of bytes used (approximation for MVP)

pub fn num_bits(&self) -> u64

Get the number of bits used (approximation for MVP)

pub fn locate(&self, pos: u64) -> Option<(u64, u64)>

Binary search to find which string contains a given absolute position. Returns (string_id, string_begin) where offsets[string_id] <= pos < offsets[string_id + 1]. This matches the C++ decoded_offsets::offset_to_id / Elias-Fano locate approach.

pub fn locate_branchless(&self, pos: u64) -> Option<(u64, u64)>

Branchless binary search variant for benchmarking comparison.

Uses conditional moves instead of branches to avoid branch mispredictions. The inner loop has no data-dependent branches - only a CMOV.

Trait Implementations

impl AlignHash for OffsetsVector

where Vec<u64>: SerInner<SerType: AlignHash>,

fn align_hash(hasher: &mut impl Hasher, offset_of: &mut usize)

Accumulates alignment information in hasher assuming to be positioned at offset_of.

fn align_hash_val(&self, hasher: &mut impl Hasher, offset_of: &mut usize)

Calls AlignHash::align_hash on a value.

impl Clone for OffsetsVector

fn clone(&self) -> OffsetsVector

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl CopyType for OffsetsVector

type Copy = Deep

impl Debug for OffsetsVector

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

Formats the value using the given formatter.

impl Default for OffsetsVector

fn default() -> Self

Returns the “default value” for a type.

impl DeserInner for OffsetsVector

where Vec<u64>: DeserInner,

type DeserType<'__epserde_desertype> = OffsetsVector

The deserialization type associated with this type. It can be retrieved conveniently with the alias DeserType.

unsafe fn _deser_full_inner( backend: &mut impl ReadWithPos, ) -> Result<Self, Error>

Safety

unsafe fn _deser_eps_inner<'deser_eps_inner_lifetime>( backend: &mut SliceWithPos<'deser_eps_inner_lifetime>, ) -> Result<Self::DeserType<'deser_eps_inner_lifetime>, Error>

Safety

impl SerInner for OffsetsVector

where Vec<u64>: SerInner,

const IS_ZERO_COPY: bool

Inner constant used by the derive macros to keep track recursively of whether the type satisfies the conditions for being zero-copy. It is checked at runtime against the trait implemented by the type, and if a ZeroCopy type has this constant set to false serialization will panic.

type SerType = OffsetsVector

This is the type that will be written in the header of the file, and thus the type that will be deserialized. In most cases it is Self, but in some cases, as for references to slices, it is customized.

unsafe fn _ser_inner(&self, backend: &mut impl WriteWithNames) -> Result<()>

Serializes this structure using the given backend.

impl TypeHash for OffsetsVector

where Vec<u64>: SerInner<SerType: TypeHash>,

fn type_hash(hasher: &mut impl Hasher)

Accumulates type information in hasher.

fn type_hash_val(&self, hasher: &mut impl Hasher)

Calls TypeHash::type_hash on a value.