Struct zerovec::flexzerovec::slice::FlexZeroSlice
source · #[repr(C, packed(1))]pub struct FlexZeroSlice {
width: u8,
data: [u8],
}
Expand description
A zero-copy “slice” that efficiently represents [usize]
.
Fields§
§width: u8
§data: [u8]
Implementations§
source§impl FlexZeroSlice
impl FlexZeroSlice
sourcepub const fn new_empty() -> &'static Self
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);
sourcepub const fn parse_byte_slice(bytes: &[u8]) -> Result<&Self, ZeroVecError>
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));
sourcepub const unsafe fn from_byte_slice_unchecked(bytes: &[u8]) -> &Self
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.
pub(crate) unsafe fn from_byte_slice_mut_unchecked( bytes: &mut [u8], ) -> &mut Self
sourcepub fn as_bytes(&self) -> &[u8] ⓘ
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());
sourcepub const fn as_flexzerovec(&self) -> FlexZeroVec<'_>
pub const fn as_flexzerovec(&self) -> FlexZeroVec<'_>
Borrows this FlexZeroSlice
as a FlexZeroVec::Borrowed
.
pub(crate) fn get_width(&self) -> usize
sourcepub fn get(&self, index: usize) -> Option<usize>
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);
sourcepub(crate) fn get_chunk(&self, index: usize) -> Option<&[u8]>
pub(crate) fn get_chunk(&self, index: usize) -> Option<&[u8]>
Gets the element at index
as a chunk of bytes, or None
if index >= self.len()
.
sourcepub unsafe fn get_unchecked(&self, index: usize) -> usize
pub unsafe fn get_unchecked(&self, index: usize) -> usize
sourcepub fn first(&self) -> Option<usize>
pub fn first(&self) -> Option<usize>
Gets the first element of the slice, or None
if the slice is empty.
sourcepub fn last(&self) -> Option<usize>
pub fn last(&self) -> Option<usize>
Gets the last element of the slice, or None
if the slice is empty.
sourcepub fn iter(
&self,
) -> impl DoubleEndedIterator<Item = usize> + '_ + ExactSizeIterator<Item = usize>
pub fn iter( &self, ) -> impl DoubleEndedIterator<Item = usize> + '_ + ExactSizeIterator<Item = usize>
Gets an iterator over the elements of the slice as usize
.
sourcepub fn iter_pairs(&self) -> impl Iterator<Item = (usize, Option<usize>)> + '_
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);
sourcepub fn to_vec(&self) -> Vec<usize>
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());
sourcepub fn binary_search(&self, needle: usize) -> Result<usize, usize>
pub fn binary_search(&self, needle: usize) -> Result<usize, usize>
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));
sourcepub fn binary_search_in_range(
&self,
needle: usize,
range: Range<usize>,
) -> Option<Result<usize, usize>>
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);
sourcepub fn binary_search_by(
&self,
predicate: impl FnMut(usize) -> Ordering,
) -> Result<usize, usize>
pub fn binary_search_by( &self, predicate: impl FnMut(usize) -> Ordering, ) -> Result<usize, usize>
Binary searches a sorted FlexZeroSlice
according to a predicate function.
sourcepub fn binary_search_in_range_by(
&self,
predicate: impl FnMut(usize) -> Ordering,
range: Range<usize>,
) -> Option<Result<usize, usize>>
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.
sourcepub fn binary_search_with_index(
&self,
predicate: impl FnMut(usize) -> Ordering,
) -> Result<usize, usize>
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
.
sourcepub fn binary_search_in_range_with_index(
&self,
predicate: impl FnMut(usize) -> Ordering,
range: Range<usize>,
) -> Option<Result<usize, usize>>
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.
source§impl FlexZeroSlice
impl FlexZeroSlice
sourcepub(crate) fn get_insert_info(&self, new_item: usize) -> InsertInfo
pub(crate) fn get_insert_info(&self, new_item: usize) -> InsertInfo
Compute the InsertInfo
for inserting the specified item anywhere into the vector.
§Panics
Panics if inserting the element would require allocating more than usize::MAX
bytes.
sourcepub(crate) fn insert_impl(
&mut self,
insert_info: InsertInfo,
insert_index: usize,
)
pub(crate) fn insert_impl( &mut self, insert_info: InsertInfo, insert_index: usize, )
This function should be called on a slice with a data array new_data_len
long
which previously held new_count - 1
elements.
After calling this function, all bytes in the slice will have been written.
source§impl FlexZeroSlice
impl FlexZeroSlice
sourcepub(crate) fn get_remove_info(&self, remove_index: usize) -> RemoveInfo
pub(crate) fn get_remove_info(&self, remove_index: usize) -> RemoveInfo
Compute the RemoveInfo
for removing the item at the specified index.
sourcepub(crate) fn get_sorted_pop_info(&self) -> RemoveInfo
pub(crate) fn get_sorted_pop_info(&self) -> RemoveInfo
Returns the RemoveInfo
for removing the last element. Should be called
on a slice sorted in ascending order.
This is more efficient than get_remove_info()
because it doesn’t require a
linear traversal of the vector in order to calculate new_width
.
sourcepub(crate) fn remove_impl(&mut self, remove_info: RemoveInfo)
pub(crate) fn remove_impl(&mut self, remove_info: RemoveInfo)
This function should be called on a valid slice.
After calling this function, the slice data should be truncated to new_data_len
bytes.
Trait Implementations§
source§impl<'a> AsRef<FlexZeroSlice> for FlexZeroVec<'a>
impl<'a> AsRef<FlexZeroSlice> for FlexZeroVec<'a>
source§fn as_ref(&self) -> &FlexZeroSlice
fn as_ref(&self) -> &FlexZeroSlice
source§impl Debug for FlexZeroSlice
impl Debug for FlexZeroSlice
source§impl From<&FlexZeroSlice> for FlexZeroVecOwned
impl From<&FlexZeroSlice> for FlexZeroVecOwned
source§fn from(other: &FlexZeroSlice) -> Self
fn from(other: &FlexZeroSlice) -> Self
source§impl PartialEq for FlexZeroSlice
impl PartialEq for FlexZeroSlice
source§impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for &'zf FlexZeroSlice
impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for &'zf FlexZeroSlice
source§fn zero_from(other: &'zf FlexZeroSlice) -> Self
fn zero_from(other: &'zf FlexZeroSlice) -> Self
C
into a struct that may retain references into C
.source§impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for FlexZeroVec<'zf>
impl<'zf> ZeroFrom<'zf, FlexZeroSlice> for FlexZeroVec<'zf>
source§fn zero_from(other: &'zf FlexZeroSlice) -> Self
fn zero_from(other: &'zf FlexZeroSlice) -> Self
C
into a struct that may retain references into C
.source§impl ZeroVecLike<usize> for FlexZeroSlice
impl ZeroVecLike<usize> for FlexZeroSlice
§type SliceVariant = FlexZeroSlice
type SliceVariant = FlexZeroSlice
source§fn zvl_new_borrowed() -> &'static Self::SliceVariant
fn zvl_new_borrowed() -> &'static Self::SliceVariant
source§fn zvl_binary_search(&self, k: &usize) -> Result<usize, usize>
fn zvl_binary_search(&self, k: &usize) -> Result<usize, usize>
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>>
fn zvl_binary_search_in_range( &self, k: &usize, range: Range<usize>, ) -> Option<Result<usize, usize>>
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>
fn zvl_binary_search_by( &self, predicate: impl FnMut(&usize) -> Ordering, ) -> Result<usize, usize>
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>>
fn zvl_binary_search_in_range_by( &self, predicate: impl FnMut(&usize) -> Ordering, range: Range<usize>, ) -> Option<Result<usize, usize>>
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_as_borrowed(&self) -> &FlexZeroSlice
fn zvl_as_borrowed(&self) -> &FlexZeroSlice
&self
. Read moresource§fn zvl_get_as_t<R>(g: &Self::GetType, f: impl FnOnce(&usize) -> R) -> R
fn zvl_get_as_t<R>(g: &Self::GetType, f: impl FnOnce(&usize) -> R) -> R
source§fn zvl_is_ascending(&self) -> boolwhere
T: Ord,
fn zvl_is_ascending(&self) -> boolwhere
T: Ord,
T
s Ord
impl