Struct zerovec::vecs::FlexZeroSlice

source ·
#[repr(C, packed(1))]
pub struct FlexZeroSlice { /* private fields */ }
Expand description

A zero-copy “slice” that efficiently represents [usize].

Implementations§

source§

impl FlexZeroSlice

source

pub const fn new_empty() -> &'static Self

Constructs a new empty FlexZeroSlice.

use zerovec::vecs::FlexZeroSlice;

const EMPTY_SLICE: &FlexZeroSlice = FlexZeroSlice::new_empty();

assert!(EMPTY_SLICE.is_empty());
assert_eq!(EMPTY_SLICE.len(), 0);
assert_eq!(EMPTY_SLICE.first(), None);
source

pub const fn parse_byte_slice(bytes: &[u8]) -> Result<&Self, ZeroVecError>

Safely constructs a FlexZeroSlice from a byte array.

§Examples
use zerovec::vecs::FlexZeroSlice;

const FZS: &FlexZeroSlice = match FlexZeroSlice::parse_byte_slice(&[
    2, // width
    0x42, 0x00, // first value
    0x07, 0x09, // second value
    0xFF, 0xFF, // third value
]) {
    Ok(v) => v,
    Err(_) => panic!("invalid bytes"),
};

assert!(!FZS.is_empty());
assert_eq!(FZS.len(), 3);
assert_eq!(FZS.first(), Some(0x0042));
assert_eq!(FZS.get(0), Some(0x0042));
assert_eq!(FZS.get(1), Some(0x0907));
assert_eq!(FZS.get(2), Some(0xFFFF));
assert_eq!(FZS.get(3), None);
assert_eq!(FZS.last(), Some(0xFFFF));
source

pub const unsafe fn from_byte_slice_unchecked(bytes: &[u8]) -> &Self

Constructs a FlexZeroSlice without checking invariants.

§Panics

Panics if bytes is empty.

§Safety

Must be called on a valid FlexZeroSlice byte array.

source

pub fn as_bytes(&self) -> &[u8]

Returns this slice as its underlying &[u8] byte buffer representation.

Useful for serialization.

§Example
use zerovec::vecs::FlexZeroSlice;

let bytes: &[u8] = &[2, 0xD3, 0x00, 0x19, 0x01, 0xA5, 0x01, 0xCD, 0x80];
let fzv = FlexZeroSlice::parse_byte_slice(bytes).expect("valid bytes");

assert_eq!(bytes, fzv.as_bytes());
source

pub const fn as_flexzerovec(&self) -> FlexZeroVec<'_>

Borrows this FlexZeroSlice as a FlexZeroVec::Borrowed.

source

pub fn len(&self) -> usize

Returns the number of elements in the FlexZeroSlice.

source

pub fn is_empty(&self) -> bool

Returns whether there are zero elements in the FlexZeroSlice.

source

pub fn get(&self, index: usize) -> Option<usize>

Gets the element at index, or None if index >= self.len().

§Examples
use zerovec::vecs::FlexZeroVec;

let fzv: FlexZeroVec = [22, 33].iter().copied().collect();
assert_eq!(fzv.get(0), Some(22));
assert_eq!(fzv.get(1), Some(33));
assert_eq!(fzv.get(2), None);
source

pub unsafe fn get_unchecked(&self, index: usize) -> usize

Gets the element at index without checking bounds.

§Safety

index must be in-range.

source

pub fn first(&self) -> Option<usize>

Gets the first element of the slice, or None if the slice is empty.

source

pub fn last(&self) -> Option<usize>

Gets the last element of the slice, or None if the slice is empty.

source

pub fn iter( &self, ) -> impl DoubleEndedIterator<Item = usize> + '_ + ExactSizeIterator<Item = usize>

Gets an iterator over the elements of the slice as usize.

source

pub fn iter_pairs(&self) -> impl Iterator<Item = (usize, Option<usize>)> + '_

Gets an iterator over pairs of elements.

The second element of the final pair is None.

§Examples
use zerovec::vecs::FlexZeroVec;

let nums: &[usize] = &[211, 281, 421, 461];
let fzv: FlexZeroVec = nums.iter().copied().collect();

let mut pairs_it = fzv.iter_pairs();

assert_eq!(pairs_it.next(), Some((211, Some(281))));
assert_eq!(pairs_it.next(), Some((281, Some(421))));
assert_eq!(pairs_it.next(), Some((421, Some(461))));
assert_eq!(pairs_it.next(), Some((461, None)));
assert_eq!(pairs_it.next(), None);
source

pub fn to_vec(&self) -> Vec<usize>

Creates a Vec<usize> from a FlexZeroSlice (or FlexZeroVec).

§Examples
use zerovec::vecs::FlexZeroVec;

let nums: &[usize] = &[211, 281, 421, 461];
let fzv: FlexZeroVec = nums.iter().copied().collect();
let vec: Vec<usize> = fzv.to_vec();

assert_eq!(nums, vec.as_slice());

Binary searches a sorted FlexZeroSlice for the given usize value.

§Examples
use zerovec::vecs::FlexZeroVec;

let nums: &[usize] = &[211, 281, 421, 461];
let fzv: FlexZeroVec = nums.iter().copied().collect();

assert_eq!(fzv.binary_search(0), Err(0));
assert_eq!(fzv.binary_search(211), Ok(0));
assert_eq!(fzv.binary_search(250), Err(1));
assert_eq!(fzv.binary_search(281), Ok(1));
assert_eq!(fzv.binary_search(300), Err(2));
assert_eq!(fzv.binary_search(421), Ok(2));
assert_eq!(fzv.binary_search(450), Err(3));
assert_eq!(fzv.binary_search(461), Ok(3));
assert_eq!(fzv.binary_search(462), Err(4));
source

pub fn binary_search_in_range( &self, needle: usize, range: Range<usize>, ) -> Option<Result<usize, usize>>

Binary searches a sorted range of a FlexZeroSlice for the given usize value.

The indices in the return value are relative to the start of the range.

§Examples
use zerovec::vecs::FlexZeroVec;

// Make a FlexZeroVec with two sorted ranges: 0..3 and 3..5
let nums: &[usize] = &[111, 222, 444, 333, 555];
let fzv: FlexZeroVec = nums.iter().copied().collect();

// Search in the first range:
assert_eq!(fzv.binary_search_in_range(0, 0..3), Some(Err(0)));
assert_eq!(fzv.binary_search_in_range(111, 0..3), Some(Ok(0)));
assert_eq!(fzv.binary_search_in_range(199, 0..3), Some(Err(1)));
assert_eq!(fzv.binary_search_in_range(222, 0..3), Some(Ok(1)));
assert_eq!(fzv.binary_search_in_range(399, 0..3), Some(Err(2)));
assert_eq!(fzv.binary_search_in_range(444, 0..3), Some(Ok(2)));
assert_eq!(fzv.binary_search_in_range(999, 0..3), Some(Err(3)));

// Search in the second range:
assert_eq!(fzv.binary_search_in_range(0, 3..5), Some(Err(0)));
assert_eq!(fzv.binary_search_in_range(333, 3..5), Some(Ok(0)));
assert_eq!(fzv.binary_search_in_range(399, 3..5), Some(Err(1)));
assert_eq!(fzv.binary_search_in_range(555, 3..5), Some(Ok(1)));
assert_eq!(fzv.binary_search_in_range(999, 3..5), Some(Err(2)));

// Out-of-bounds range:
assert_eq!(fzv.binary_search_in_range(0, 4..6), None);
source

pub fn binary_search_by( &self, predicate: impl FnMut(usize) -> Ordering, ) -> Result<usize, usize>

Binary searches a sorted FlexZeroSlice according to a predicate function.

source

pub fn binary_search_in_range_by( &self, predicate: impl FnMut(usize) -> Ordering, range: Range<usize>, ) -> Option<Result<usize, usize>>

Binary searches a sorted range of a FlexZeroSlice according to a predicate function.

The indices in the return value are relative to the start of the range.

source

pub fn binary_search_with_index( &self, predicate: impl FnMut(usize) -> Ordering, ) -> Result<usize, usize>

Binary searches a FlexZeroSlice by its indices.

The predicate function is passed in-bounds indices into the FlexZeroSlice.

source

pub fn binary_search_in_range_with_index( &self, predicate: impl FnMut(usize) -> Ordering, range: Range<usize>, ) -> Option<Result<usize, usize>>

Binary searches a range of a FlexZeroSlice by its indices.

The predicate function is passed in-bounds indices into the FlexZeroSlice, which are relative to the start of the entire slice.

The indices in the return value are relative to the start of the range.

Trait Implementations§

source§

impl<'a> AsRef<FlexZeroSlice> for FlexZeroVec<'a>

source§

fn as_ref(&self) -> &FlexZeroSlice

Converts this type into a shared reference of the (usually inferred) input type.
source§

impl Debug for FlexZeroSlice

source§

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

Formats the value using the given formatter. Read more
source§

impl From<&FlexZeroSlice> for FlexZeroVecOwned

source§

fn from(other: &FlexZeroSlice) -> Self

Converts to this type from the input type.
source§

impl PartialEq for FlexZeroSlice

source§

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

Tests for self and other values to be equal, and is used by ==.
1.0.0 · source§

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

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

impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for &'zf FlexZeroSlice

source§

fn zero_from(other: &'zf FlexZeroSlice) -> Self

Clone the other C into a struct that may retain references into C.
source§

impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for FlexZeroVec<'zf>

source§

fn zero_from(other: &'zf FlexZeroSlice) -> Self

Clone the other C into a struct that may retain references into C.
source§

impl ZeroVecLike<usize> for FlexZeroSlice

source§

type GetType = [u8]

The type returned by Self::get()
source§

type SliceVariant = FlexZeroSlice

A fully borrowed version of this
source§

fn zvl_new_borrowed() -> &'static Self::SliceVariant

Create a new, empty borrowed variant
Search for a key in a sorted vector, returns Ok(index) if found, returns Err(insert_index) if not found, where insert_index is the index where it should be inserted to maintain sort order.
source§

fn zvl_binary_search_in_range( &self, k: &usize, range: Range<usize>, ) -> Option<Result<usize, usize>>

Search for a key within a certain range in a sorted vector. Returns None if the range is out of bounds, and Ok or Err in the same way as zvl_binary_search. Indices are returned relative to the start of the range.
source§

fn zvl_binary_search_by( &self, predicate: impl FnMut(&usize) -> Ordering, ) -> Result<usize, usize>

Search for a key in a sorted vector by a predicate, returns Ok(index) if found, returns Err(insert_index) if not found, where insert_index is the index where it should be inserted to maintain sort order.
source§

fn zvl_binary_search_in_range_by( &self, predicate: impl FnMut(&usize) -> Ordering, range: Range<usize>, ) -> Option<Result<usize, usize>>

Search for a key within a certain range in a sorted vector by a predicate. Returns None if the range is out of bounds, and Ok or Err in the same way as zvl_binary_search. Indices are returned relative to the start of the range.
source§

fn zvl_get(&self, index: usize) -> Option<&[u8]>

Get element at index
source§

fn zvl_len(&self) -> usize

The length of this vector
source§

fn zvl_as_borrowed(&self) -> &FlexZeroSlice

Construct a borrowed variant by borrowing from &self. Read more
source§

fn zvl_get_as_t<R>(g: &Self::GetType, f: impl FnOnce(&usize) -> R) -> R

Obtain a reference to T, passed to a closure Read more
source§

fn zvl_is_ascending(&self) -> bool
where T: Ord,

Check if this vector is in ascending order according to Ts Ord impl
source§

fn zvl_is_empty(&self) -> bool

Check if this vector is empty
source§

fn t_cmp_get(t: &T, g: &Self::GetType) -> Ordering
where T: Ord,

Compare this type with a Self::GetType. This must produce the same result as if g were converted to Self
source§

fn get_cmp_get(a: &Self::GetType, b: &Self::GetType) -> Ordering
where T: Ord,

Compare two values of Self::GetType. This must produce the same result as if both a and b were converted to Self
source§

impl Eq for FlexZeroSlice

Auto Trait Implementations§

Blanket Implementations§

source§

impl<T> Any for T
where T: 'static + ?Sized,

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for T
where T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more