| |
| use std::cmp; |
| use std::iter; |
| use std::mem; |
| use std::ops::{Bound, Deref, DerefMut, RangeBounds}; |
| use std::ptr; |
| use std::slice; |
| |
| // extra traits |
| use std::borrow::{Borrow, BorrowMut}; |
| use std::hash::{Hash, Hasher}; |
| use std::fmt; |
| |
| #[cfg(feature="std")] |
| use std::io; |
| |
| use std::mem::ManuallyDrop; |
| use std::mem::MaybeUninit; |
| |
| #[cfg(feature="serde")] |
| use serde::{Serialize, Deserialize, Serializer, Deserializer}; |
| |
| use crate::LenUint; |
| use crate::errors::CapacityError; |
| use crate::arrayvec_impl::ArrayVecImpl; |
| use crate::utils::MakeMaybeUninit; |
| |
| /// A vector with a fixed capacity. |
| /// |
| /// The `ArrayVec` is a vector backed by a fixed size array. It keeps track of |
| /// the number of initialized elements. The `ArrayVec<T, CAP>` is parameterized |
| /// by `T` for the element type and `CAP` for the maximum capacity. |
| /// |
| /// `CAP` is of type `usize` but is range limited to `u32::MAX`; attempting to create larger |
| /// arrayvecs with larger capacity will panic. |
| /// |
| /// The vector is a contiguous value (storing the elements inline) that you can store directly on |
| /// the stack if needed. |
| /// |
| /// It offers a simple API but also dereferences to a slice, so that the full slice API is |
| /// available. The ArrayVec can be converted into a by value iterator. |
| #[repr(C)] |
| pub struct ArrayVec<T, const CAP: usize> { |
| len: LenUint, |
| // the `len` first elements of the array are initialized |
| xs: [MaybeUninit<T>; CAP], |
| } |
| |
| impl<T, const CAP: usize> Drop for ArrayVec<T, CAP> { |
| fn drop(&mut self) { |
| self.clear(); |
| |
| // MaybeUninit inhibits array's drop |
| } |
| } |
| |
| macro_rules! panic_oob { |
| ($method_name:expr, $index:expr, $len:expr) => { |
| panic!(concat!("ArrayVec::", $method_name, ": index {} is out of bounds in vector of length {}"), |
| $index, $len) |
| } |
| } |
| |
| impl<T, const CAP: usize> ArrayVec<T, CAP> { |
| /// Capacity |
| const CAPACITY: usize = CAP; |
| |
| /// Create a new empty `ArrayVec`. |
| /// |
| /// The maximum capacity is given by the generic parameter `CAP`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 16>::new(); |
| /// array.push(1); |
| /// array.push(2); |
| /// assert_eq!(&array[..], &[1, 2]); |
| /// assert_eq!(array.capacity(), 16); |
| /// ``` |
| #[inline] |
| #[track_caller] |
| pub fn new() -> ArrayVec<T, CAP> { |
| assert_capacity_limit!(CAP); |
| unsafe { |
| ArrayVec { xs: MaybeUninit::uninit().assume_init(), len: 0 } |
| } |
| } |
| |
| /// Create a new empty `ArrayVec` (const fn). |
| /// |
| /// The maximum capacity is given by the generic parameter `CAP`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// static ARRAY: ArrayVec<u8, 1024> = ArrayVec::new_const(); |
| /// ``` |
| pub const fn new_const() -> ArrayVec<T, CAP> { |
| assert_capacity_limit_const!(CAP); |
| ArrayVec { xs: MakeMaybeUninit::ARRAY, len: 0 } |
| } |
| |
| /// Return the number of elements in the `ArrayVec`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// array.pop(); |
| /// assert_eq!(array.len(), 2); |
| /// ``` |
| #[inline(always)] |
| pub const fn len(&self) -> usize { self.len as usize } |
| |
| /// Returns whether the `ArrayVec` is empty. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1]); |
| /// array.pop(); |
| /// assert_eq!(array.is_empty(), true); |
| /// ``` |
| #[inline] |
| pub const fn is_empty(&self) -> bool { self.len() == 0 } |
| |
| /// Return the capacity of the `ArrayVec`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let array = ArrayVec::from([1, 2, 3]); |
| /// assert_eq!(array.capacity(), 3); |
| /// ``` |
| #[inline(always)] |
| pub const fn capacity(&self) -> usize { CAP } |
| |
| /// Return true if the `ArrayVec` is completely filled to its capacity, false otherwise. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 1>::new(); |
| /// assert!(!array.is_full()); |
| /// array.push(1); |
| /// assert!(array.is_full()); |
| /// ``` |
| pub const fn is_full(&self) -> bool { self.len() == self.capacity() } |
| |
| /// Returns the capacity left in the `ArrayVec`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// array.pop(); |
| /// assert_eq!(array.remaining_capacity(), 1); |
| /// ``` |
| pub const fn remaining_capacity(&self) -> usize { |
| self.capacity() - self.len() |
| } |
| |
| /// Push `element` to the end of the vector. |
| /// |
| /// ***Panics*** if the vector is already full. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// array.push(1); |
| /// array.push(2); |
| /// |
| /// assert_eq!(&array[..], &[1, 2]); |
| /// ``` |
| #[track_caller] |
| pub fn push(&mut self, element: T) { |
| ArrayVecImpl::push(self, element) |
| } |
| |
| /// Push `element` to the end of the vector. |
| /// |
| /// Return `Ok` if the push succeeds, or return an error if the vector |
| /// is already full. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// let push1 = array.try_push(1); |
| /// let push2 = array.try_push(2); |
| /// |
| /// assert!(push1.is_ok()); |
| /// assert!(push2.is_ok()); |
| /// |
| /// assert_eq!(&array[..], &[1, 2]); |
| /// |
| /// let overflow = array.try_push(3); |
| /// |
| /// assert!(overflow.is_err()); |
| /// ``` |
| pub fn try_push(&mut self, element: T) -> Result<(), CapacityError<T>> { |
| ArrayVecImpl::try_push(self, element) |
| } |
| |
| /// Push `element` to the end of the vector without checking the capacity. |
| /// |
| /// It is up to the caller to ensure the capacity of the vector is |
| /// sufficiently large. |
| /// |
| /// This method uses *debug assertions* to check that the arrayvec is not full. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// if array.len() + 2 <= array.capacity() { |
| /// unsafe { |
| /// array.push_unchecked(1); |
| /// array.push_unchecked(2); |
| /// } |
| /// } |
| /// |
| /// assert_eq!(&array[..], &[1, 2]); |
| /// ``` |
| pub unsafe fn push_unchecked(&mut self, element: T) { |
| ArrayVecImpl::push_unchecked(self, element) |
| } |
| |
| /// Shortens the vector, keeping the first `len` elements and dropping |
| /// the rest. |
| /// |
| /// If `len` is greater than the vector’s current length this has no |
| /// effect. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3, 4, 5]); |
| /// array.truncate(3); |
| /// assert_eq!(&array[..], &[1, 2, 3]); |
| /// array.truncate(4); |
| /// assert_eq!(&array[..], &[1, 2, 3]); |
| /// ``` |
| pub fn truncate(&mut self, new_len: usize) { |
| ArrayVecImpl::truncate(self, new_len) |
| } |
| |
| /// Remove all elements in the vector. |
| pub fn clear(&mut self) { |
| ArrayVecImpl::clear(self) |
| } |
| |
| |
| /// Get pointer to where element at `index` would be |
| unsafe fn get_unchecked_ptr(&mut self, index: usize) -> *mut T { |
| self.as_mut_ptr().add(index) |
| } |
| |
| /// Insert `element` at position `index`. |
| /// |
| /// Shift up all elements after `index`. |
| /// |
| /// It is an error if the index is greater than the length or if the |
| /// arrayvec is full. |
| /// |
| /// ***Panics*** if the array is full or the `index` is out of bounds. See |
| /// `try_insert` for fallible version. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// array.insert(0, "x"); |
| /// array.insert(0, "y"); |
| /// assert_eq!(&array[..], &["y", "x"]); |
| /// |
| /// ``` |
| #[track_caller] |
| pub fn insert(&mut self, index: usize, element: T) { |
| self.try_insert(index, element).unwrap() |
| } |
| |
| /// Insert `element` at position `index`. |
| /// |
| /// Shift up all elements after `index`; the `index` must be less than |
| /// or equal to the length. |
| /// |
| /// Returns an error if vector is already at full capacity. |
| /// |
| /// ***Panics*** `index` is out of bounds. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// assert!(array.try_insert(0, "x").is_ok()); |
| /// assert!(array.try_insert(0, "y").is_ok()); |
| /// assert!(array.try_insert(0, "z").is_err()); |
| /// assert_eq!(&array[..], &["y", "x"]); |
| /// |
| /// ``` |
| pub fn try_insert(&mut self, index: usize, element: T) -> Result<(), CapacityError<T>> { |
| if index > self.len() { |
| panic_oob!("try_insert", index, self.len()) |
| } |
| if self.len() == self.capacity() { |
| return Err(CapacityError::new(element)); |
| } |
| let len = self.len(); |
| |
| // follows is just like Vec<T> |
| unsafe { // infallible |
| // The spot to put the new value |
| { |
| let p: *mut _ = self.get_unchecked_ptr(index); |
| // Shift everything over to make space. (Duplicating the |
| // `index`th element into two consecutive places.) |
| ptr::copy(p, p.offset(1), len - index); |
| // Write it in, overwriting the first copy of the `index`th |
| // element. |
| ptr::write(p, element); |
| } |
| self.set_len(len + 1); |
| } |
| Ok(()) |
| } |
| |
| /// Remove the last element in the vector and return it. |
| /// |
| /// Return `Some(` *element* `)` if the vector is non-empty, else `None`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::<_, 2>::new(); |
| /// |
| /// array.push(1); |
| /// |
| /// assert_eq!(array.pop(), Some(1)); |
| /// assert_eq!(array.pop(), None); |
| /// ``` |
| pub fn pop(&mut self) -> Option<T> { |
| ArrayVecImpl::pop(self) |
| } |
| |
| /// Remove the element at `index` and swap the last element into its place. |
| /// |
| /// This operation is O(1). |
| /// |
| /// Return the *element* if the index is in bounds, else panic. |
| /// |
| /// ***Panics*** if the `index` is out of bounds. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// assert_eq!(array.swap_remove(0), 1); |
| /// assert_eq!(&array[..], &[3, 2]); |
| /// |
| /// assert_eq!(array.swap_remove(1), 2); |
| /// assert_eq!(&array[..], &[3]); |
| /// ``` |
| pub fn swap_remove(&mut self, index: usize) -> T { |
| self.swap_pop(index) |
| .unwrap_or_else(|| { |
| panic_oob!("swap_remove", index, self.len()) |
| }) |
| } |
| |
| /// Remove the element at `index` and swap the last element into its place. |
| /// |
| /// This is a checked version of `.swap_remove`. |
| /// This operation is O(1). |
| /// |
| /// Return `Some(` *element* `)` if the index is in bounds, else `None`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// assert_eq!(array.swap_pop(0), Some(1)); |
| /// assert_eq!(&array[..], &[3, 2]); |
| /// |
| /// assert_eq!(array.swap_pop(10), None); |
| /// ``` |
| pub fn swap_pop(&mut self, index: usize) -> Option<T> { |
| let len = self.len(); |
| if index >= len { |
| return None; |
| } |
| self.swap(index, len - 1); |
| self.pop() |
| } |
| |
| /// Remove the element at `index` and shift down the following elements. |
| /// |
| /// The `index` must be strictly less than the length of the vector. |
| /// |
| /// ***Panics*** if the `index` is out of bounds. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// let removed_elt = array.remove(0); |
| /// assert_eq!(removed_elt, 1); |
| /// assert_eq!(&array[..], &[2, 3]); |
| /// ``` |
| pub fn remove(&mut self, index: usize) -> T { |
| self.pop_at(index) |
| .unwrap_or_else(|| { |
| panic_oob!("remove", index, self.len()) |
| }) |
| } |
| |
| /// Remove the element at `index` and shift down the following elements. |
| /// |
| /// This is a checked version of `.remove(index)`. Returns `None` if there |
| /// is no element at `index`. Otherwise, return the element inside `Some`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// assert!(array.pop_at(0).is_some()); |
| /// assert_eq!(&array[..], &[2, 3]); |
| /// |
| /// assert!(array.pop_at(2).is_none()); |
| /// assert!(array.pop_at(10).is_none()); |
| /// ``` |
| pub fn pop_at(&mut self, index: usize) -> Option<T> { |
| if index >= self.len() { |
| None |
| } else { |
| self.drain(index..index + 1).next() |
| } |
| } |
| |
| /// Retains only the elements specified by the predicate. |
| /// |
| /// In other words, remove all elements `e` such that `f(&mut e)` returns false. |
| /// This method operates in place and preserves the order of the retained |
| /// elements. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3, 4]); |
| /// array.retain(|x| *x & 1 != 0 ); |
| /// assert_eq!(&array[..], &[1, 3]); |
| /// ``` |
| pub fn retain<F>(&mut self, mut f: F) |
| where F: FnMut(&mut T) -> bool |
| { |
| // Check the implementation of |
| // https://doc.rust-lang.org/std/vec/struct.Vec.html#method.retain |
| // for safety arguments (especially regarding panics in f and when |
| // dropping elements). Implementation closely mirrored here. |
| |
| let original_len = self.len(); |
| unsafe { self.set_len(0) }; |
| |
| struct BackshiftOnDrop<'a, T, const CAP: usize> { |
| v: &'a mut ArrayVec<T, CAP>, |
| processed_len: usize, |
| deleted_cnt: usize, |
| original_len: usize, |
| } |
| |
| impl<T, const CAP: usize> Drop for BackshiftOnDrop<'_, T, CAP> { |
| fn drop(&mut self) { |
| if self.deleted_cnt > 0 { |
| unsafe { |
| ptr::copy( |
| self.v.as_ptr().add(self.processed_len), |
| self.v.as_mut_ptr().add(self.processed_len - self.deleted_cnt), |
| self.original_len - self.processed_len |
| ); |
| } |
| } |
| unsafe { |
| self.v.set_len(self.original_len - self.deleted_cnt); |
| } |
| } |
| } |
| |
| let mut g = BackshiftOnDrop { v: self, processed_len: 0, deleted_cnt: 0, original_len }; |
| |
| #[inline(always)] |
| fn process_one<F: FnMut(&mut T) -> bool, T, const CAP: usize, const DELETED: bool>( |
| f: &mut F, |
| g: &mut BackshiftOnDrop<'_, T, CAP> |
| ) -> bool { |
| let cur = unsafe { g.v.as_mut_ptr().add(g.processed_len) }; |
| if !f(unsafe { &mut *cur }) { |
| g.processed_len += 1; |
| g.deleted_cnt += 1; |
| unsafe { ptr::drop_in_place(cur) }; |
| return false; |
| } |
| if DELETED { |
| unsafe { |
| let hole_slot = cur.sub(g.deleted_cnt); |
| ptr::copy_nonoverlapping(cur, hole_slot, 1); |
| } |
| } |
| g.processed_len += 1; |
| true |
| } |
| |
| // Stage 1: Nothing was deleted. |
| while g.processed_len != original_len { |
| if !process_one::<F, T, CAP, false>(&mut f, &mut g) { |
| break; |
| } |
| } |
| |
| // Stage 2: Some elements were deleted. |
| while g.processed_len != original_len { |
| process_one::<F, T, CAP, true>(&mut f, &mut g); |
| } |
| |
| drop(g); |
| } |
| |
| /// Set the vector’s length without dropping or moving out elements |
| /// |
| /// This method is `unsafe` because it changes the notion of the |
| /// number of “valid” elements in the vector. Use with care. |
| /// |
| /// This method uses *debug assertions* to check that `length` is |
| /// not greater than the capacity. |
| pub unsafe fn set_len(&mut self, length: usize) { |
| // type invariant that capacity always fits in LenUint |
| debug_assert!(length <= self.capacity()); |
| self.len = length as LenUint; |
| } |
| |
| /// Copy all elements from the slice and append to the `ArrayVec`. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut vec: ArrayVec<usize, 10> = ArrayVec::new(); |
| /// vec.push(1); |
| /// vec.try_extend_from_slice(&[2, 3]).unwrap(); |
| /// assert_eq!(&vec[..], &[1, 2, 3]); |
| /// ``` |
| /// |
| /// # Errors |
| /// |
| /// This method will return an error if the capacity left (see |
| /// [`remaining_capacity`]) is smaller then the length of the provided |
| /// slice. |
| /// |
| /// [`remaining_capacity`]: #method.remaining_capacity |
| pub fn try_extend_from_slice(&mut self, other: &[T]) -> Result<(), CapacityError> |
| where T: Copy, |
| { |
| if self.remaining_capacity() < other.len() { |
| return Err(CapacityError::new(())); |
| } |
| |
| let self_len = self.len(); |
| let other_len = other.len(); |
| |
| unsafe { |
| let dst = self.get_unchecked_ptr(self_len); |
| ptr::copy_nonoverlapping(other.as_ptr(), dst, other_len); |
| self.set_len(self_len + other_len); |
| } |
| Ok(()) |
| } |
| |
| /// Create a draining iterator that removes the specified range in the vector |
| /// and yields the removed items from start to end. The element range is |
| /// removed even if the iterator is not consumed until the end. |
| /// |
| /// Note: It is unspecified how many elements are removed from the vector, |
| /// if the `Drain` value is leaked. |
| /// |
| /// **Panics** if the starting point is greater than the end point or if |
| /// the end point is greater than the length of the vector. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut v1 = ArrayVec::from([1, 2, 3]); |
| /// let v2: ArrayVec<_, 3> = v1.drain(0..2).collect(); |
| /// assert_eq!(&v1[..], &[3]); |
| /// assert_eq!(&v2[..], &[1, 2]); |
| /// ``` |
| pub fn drain<R>(&mut self, range: R) -> Drain<T, CAP> |
| where R: RangeBounds<usize> |
| { |
| // Memory safety |
| // |
| // When the Drain is first created, it shortens the length of |
| // the source vector to make sure no uninitialized or moved-from elements |
| // are accessible at all if the Drain's destructor never gets to run. |
| // |
| // Drain will ptr::read out the values to remove. |
| // When finished, remaining tail of the vec is copied back to cover |
| // the hole, and the vector length is restored to the new length. |
| // |
| let len = self.len(); |
| let start = match range.start_bound() { |
| Bound::Unbounded => 0, |
| Bound::Included(&i) => i, |
| Bound::Excluded(&i) => i.saturating_add(1), |
| }; |
| let end = match range.end_bound() { |
| Bound::Excluded(&j) => j, |
| Bound::Included(&j) => j.saturating_add(1), |
| Bound::Unbounded => len, |
| }; |
| self.drain_range(start, end) |
| } |
| |
| fn drain_range(&mut self, start: usize, end: usize) -> Drain<T, CAP> |
| { |
| let len = self.len(); |
| |
| // bounds check happens here (before length is changed!) |
| let range_slice: *const _ = &self[start..end]; |
| |
| // Calling `set_len` creates a fresh and thus unique mutable references, making all |
| // older aliases we created invalid. So we cannot call that function. |
| self.len = start as LenUint; |
| |
| unsafe { |
| Drain { |
| tail_start: end, |
| tail_len: len - end, |
| iter: (*range_slice).iter(), |
| vec: self as *mut _, |
| } |
| } |
| } |
| |
| /// Return the inner fixed size array, if it is full to its capacity. |
| /// |
| /// Return an `Ok` value with the array if length equals capacity, |
| /// return an `Err` with self otherwise. |
| pub fn into_inner(self) -> Result<[T; CAP], Self> { |
| if self.len() < self.capacity() { |
| Err(self) |
| } else { |
| unsafe { Ok(self.into_inner_unchecked()) } |
| } |
| } |
| |
| /// Return the inner fixed size array. |
| /// |
| /// Safety: |
| /// This operation is safe if and only if length equals capacity. |
| pub unsafe fn into_inner_unchecked(self) -> [T; CAP] { |
| debug_assert_eq!(self.len(), self.capacity()); |
| let self_ = ManuallyDrop::new(self); |
| let array = ptr::read(self_.as_ptr() as *const [T; CAP]); |
| array |
| } |
| |
| /// Returns the ArrayVec, replacing the original with a new empty ArrayVec. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut v = ArrayVec::from([0, 1, 2, 3]); |
| /// assert_eq!([0, 1, 2, 3], v.take().into_inner().unwrap()); |
| /// assert!(v.is_empty()); |
| /// ``` |
| pub fn take(&mut self) -> Self { |
| mem::replace(self, Self::new()) |
| } |
| |
| /// Return a slice containing all elements of the vector. |
| pub fn as_slice(&self) -> &[T] { |
| ArrayVecImpl::as_slice(self) |
| } |
| |
| /// Return a mutable slice containing all elements of the vector. |
| pub fn as_mut_slice(&mut self) -> &mut [T] { |
| ArrayVecImpl::as_mut_slice(self) |
| } |
| |
| /// Return a raw pointer to the vector's buffer. |
| pub fn as_ptr(&self) -> *const T { |
| ArrayVecImpl::as_ptr(self) |
| } |
| |
| /// Return a raw mutable pointer to the vector's buffer. |
| pub fn as_mut_ptr(&mut self) -> *mut T { |
| ArrayVecImpl::as_mut_ptr(self) |
| } |
| } |
| |
| impl<T, const CAP: usize> ArrayVecImpl for ArrayVec<T, CAP> { |
| type Item = T; |
| const CAPACITY: usize = CAP; |
| |
| fn len(&self) -> usize { self.len() } |
| |
| unsafe fn set_len(&mut self, length: usize) { |
| debug_assert!(length <= CAP); |
| self.len = length as LenUint; |
| } |
| |
| fn as_ptr(&self) -> *const Self::Item { |
| self.xs.as_ptr() as _ |
| } |
| |
| fn as_mut_ptr(&mut self) -> *mut Self::Item { |
| self.xs.as_mut_ptr() as _ |
| } |
| } |
| |
| impl<T, const CAP: usize> Deref for ArrayVec<T, CAP> { |
| type Target = [T]; |
| #[inline] |
| fn deref(&self) -> &Self::Target { |
| self.as_slice() |
| } |
| } |
| |
| impl<T, const CAP: usize> DerefMut for ArrayVec<T, CAP> { |
| #[inline] |
| fn deref_mut(&mut self) -> &mut Self::Target { |
| self.as_mut_slice() |
| } |
| } |
| |
| |
| /// Create an `ArrayVec` from an array. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// assert_eq!(array.len(), 3); |
| /// assert_eq!(array.capacity(), 3); |
| /// ``` |
| impl<T, const CAP: usize> From<[T; CAP]> for ArrayVec<T, CAP> { |
| #[track_caller] |
| fn from(array: [T; CAP]) -> Self { |
| let array = ManuallyDrop::new(array); |
| let mut vec = <ArrayVec<T, CAP>>::new(); |
| unsafe { |
| (&*array as *const [T; CAP] as *const [MaybeUninit<T>; CAP]) |
| .copy_to_nonoverlapping(&mut vec.xs as *mut [MaybeUninit<T>; CAP], 1); |
| vec.set_len(CAP); |
| } |
| vec |
| } |
| } |
| |
| |
| /// Try to create an `ArrayVec` from a slice. This will return an error if the slice was too big to |
| /// fit. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// use std::convert::TryInto as _; |
| /// |
| /// let array: ArrayVec<_, 4> = (&[1, 2, 3] as &[_]).try_into().unwrap(); |
| /// assert_eq!(array.len(), 3); |
| /// assert_eq!(array.capacity(), 4); |
| /// ``` |
| impl<T, const CAP: usize> std::convert::TryFrom<&[T]> for ArrayVec<T, CAP> |
| where T: Clone, |
| { |
| type Error = CapacityError; |
| |
| fn try_from(slice: &[T]) -> Result<Self, Self::Error> { |
| if Self::CAPACITY < slice.len() { |
| Err(CapacityError::new(())) |
| } else { |
| let mut array = Self::new(); |
| array.extend_from_slice(slice); |
| Ok(array) |
| } |
| } |
| } |
| |
| |
| /// Iterate the `ArrayVec` with references to each element. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// for elt in &array { |
| /// // ... |
| /// } |
| /// ``` |
| impl<'a, T: 'a, const CAP: usize> IntoIterator for &'a ArrayVec<T, CAP> { |
| type Item = &'a T; |
| type IntoIter = slice::Iter<'a, T>; |
| fn into_iter(self) -> Self::IntoIter { self.iter() } |
| } |
| |
| /// Iterate the `ArrayVec` with mutable references to each element. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// |
| /// for elt in &mut array { |
| /// // ... |
| /// } |
| /// ``` |
| impl<'a, T: 'a, const CAP: usize> IntoIterator for &'a mut ArrayVec<T, CAP> { |
| type Item = &'a mut T; |
| type IntoIter = slice::IterMut<'a, T>; |
| fn into_iter(self) -> Self::IntoIter { self.iter_mut() } |
| } |
| |
| /// Iterate the `ArrayVec` with each element by value. |
| /// |
| /// The vector is consumed by this operation. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// |
| /// for elt in ArrayVec::from([1, 2, 3]) { |
| /// // ... |
| /// } |
| /// ``` |
| impl<T, const CAP: usize> IntoIterator for ArrayVec<T, CAP> { |
| type Item = T; |
| type IntoIter = IntoIter<T, CAP>; |
| fn into_iter(self) -> IntoIter<T, CAP> { |
| IntoIter { index: 0, v: self, } |
| } |
| } |
| |
| |
| #[cfg(feature = "zeroize")] |
| /// "Best efforts" zeroing of the `ArrayVec`'s buffer when the `zeroize` feature is enabled. |
| /// |
| /// The length is set to 0, and the buffer is dropped and zeroized. |
| /// Cannot ensure that previous moves of the `ArrayVec` did not leave values on the stack. |
| /// |
| /// ``` |
| /// use arrayvec::ArrayVec; |
| /// use zeroize::Zeroize; |
| /// let mut array = ArrayVec::from([1, 2, 3]); |
| /// array.zeroize(); |
| /// assert_eq!(array.len(), 0); |
| /// let data = unsafe { core::slice::from_raw_parts(array.as_ptr(), array.capacity()) }; |
| /// assert_eq!(data, [0, 0, 0]); |
| /// ``` |
| impl<Z: zeroize::Zeroize, const CAP: usize> zeroize::Zeroize for ArrayVec<Z, CAP> { |
| fn zeroize(&mut self) { |
| // Zeroize all the contained elements. |
| self.iter_mut().zeroize(); |
| // Drop all the elements and set the length to 0. |
| self.clear(); |
| // Zeroize the backing array. |
| self.xs.zeroize(); |
| } |
| } |
| |
| /// By-value iterator for `ArrayVec`. |
| pub struct IntoIter<T, const CAP: usize> { |
| index: usize, |
| v: ArrayVec<T, CAP>, |
| } |
| impl<T, const CAP: usize> IntoIter<T, CAP> { |
| /// Returns the remaining items of this iterator as a slice. |
| pub fn as_slice(&self) -> &[T] { |
| &self.v[self.index..] |
| } |
| |
| /// Returns the remaining items of this iterator as a mutable slice. |
| pub fn as_mut_slice(&mut self) -> &mut [T] { |
| &mut self.v[self.index..] |
| } |
| } |
| |
| impl<T, const CAP: usize> Iterator for IntoIter<T, CAP> { |
| type Item = T; |
| |
| fn next(&mut self) -> Option<Self::Item> { |
| if self.index == self.v.len() { |
| None |
| } else { |
| unsafe { |
| let index = self.index; |
| self.index = index + 1; |
| Some(ptr::read(self.v.get_unchecked_ptr(index))) |
| } |
| } |
| } |
| |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| let len = self.v.len() - self.index; |
| (len, Some(len)) |
| } |
| } |
| |
| impl<T, const CAP: usize> DoubleEndedIterator for IntoIter<T, CAP> { |
| fn next_back(&mut self) -> Option<Self::Item> { |
| if self.index == self.v.len() { |
| None |
| } else { |
| unsafe { |
| let new_len = self.v.len() - 1; |
| self.v.set_len(new_len); |
| Some(ptr::read(self.v.get_unchecked_ptr(new_len))) |
| } |
| } |
| } |
| } |
| |
| impl<T, const CAP: usize> ExactSizeIterator for IntoIter<T, CAP> { } |
| |
| impl<T, const CAP: usize> Drop for IntoIter<T, CAP> { |
| fn drop(&mut self) { |
| // panic safety: Set length to 0 before dropping elements. |
| let index = self.index; |
| let len = self.v.len(); |
| unsafe { |
| self.v.set_len(0); |
| let elements = slice::from_raw_parts_mut( |
| self.v.get_unchecked_ptr(index), |
| len - index); |
| ptr::drop_in_place(elements); |
| } |
| } |
| } |
| |
| impl<T, const CAP: usize> Clone for IntoIter<T, CAP> |
| where T: Clone, |
| { |
| fn clone(&self) -> IntoIter<T, CAP> { |
| let mut v = ArrayVec::new(); |
| v.extend_from_slice(&self.v[self.index..]); |
| v.into_iter() |
| } |
| } |
| |
| impl<T, const CAP: usize> fmt::Debug for IntoIter<T, CAP> |
| where |
| T: fmt::Debug, |
| { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| f.debug_list() |
| .entries(&self.v[self.index..]) |
| .finish() |
| } |
| } |
| |
| /// A draining iterator for `ArrayVec`. |
| pub struct Drain<'a, T: 'a, const CAP: usize> { |
| /// Index of tail to preserve |
| tail_start: usize, |
| /// Length of tail |
| tail_len: usize, |
| /// Current remaining range to remove |
| iter: slice::Iter<'a, T>, |
| vec: *mut ArrayVec<T, CAP>, |
| } |
| |
| unsafe impl<'a, T: Sync, const CAP: usize> Sync for Drain<'a, T, CAP> {} |
| unsafe impl<'a, T: Send, const CAP: usize> Send for Drain<'a, T, CAP> {} |
| |
| impl<'a, T: 'a, const CAP: usize> Iterator for Drain<'a, T, CAP> { |
| type Item = T; |
| |
| fn next(&mut self) -> Option<Self::Item> { |
| self.iter.next().map(|elt| |
| unsafe { |
| ptr::read(elt as *const _) |
| } |
| ) |
| } |
| |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.iter.size_hint() |
| } |
| } |
| |
| impl<'a, T: 'a, const CAP: usize> DoubleEndedIterator for Drain<'a, T, CAP> |
| { |
| fn next_back(&mut self) -> Option<Self::Item> { |
| self.iter.next_back().map(|elt| |
| unsafe { |
| ptr::read(elt as *const _) |
| } |
| ) |
| } |
| } |
| |
| impl<'a, T: 'a, const CAP: usize> ExactSizeIterator for Drain<'a, T, CAP> {} |
| |
| impl<'a, T: 'a, const CAP: usize> Drop for Drain<'a, T, CAP> { |
| fn drop(&mut self) { |
| // len is currently 0 so panicking while dropping will not cause a double drop. |
| |
| // exhaust self first |
| while let Some(_) = self.next() { } |
| |
| if self.tail_len > 0 { |
| unsafe { |
| let source_vec = &mut *self.vec; |
| // memmove back untouched tail, update to new length |
| let start = source_vec.len(); |
| let tail = self.tail_start; |
| let ptr = source_vec.as_mut_ptr(); |
| ptr::copy(ptr.add(tail), ptr.add(start), self.tail_len); |
| source_vec.set_len(start + self.tail_len); |
| } |
| } |
| } |
| } |
| |
| struct ScopeExitGuard<T, Data, F> |
| where F: FnMut(&Data, &mut T) |
| { |
| value: T, |
| data: Data, |
| f: F, |
| } |
| |
| impl<T, Data, F> Drop for ScopeExitGuard<T, Data, F> |
| where F: FnMut(&Data, &mut T) |
| { |
| fn drop(&mut self) { |
| (self.f)(&self.data, &mut self.value) |
| } |
| } |
| |
| |
| |
| /// Extend the `ArrayVec` with an iterator. |
| /// |
| /// ***Panics*** if extending the vector exceeds its capacity. |
| impl<T, const CAP: usize> Extend<T> for ArrayVec<T, CAP> { |
| /// Extend the `ArrayVec` with an iterator. |
| /// |
| /// ***Panics*** if extending the vector exceeds its capacity. |
| #[track_caller] |
| fn extend<I: IntoIterator<Item=T>>(&mut self, iter: I) { |
| unsafe { |
| self.extend_from_iter::<_, true>(iter) |
| } |
| } |
| } |
| |
| #[inline(never)] |
| #[cold] |
| #[track_caller] |
| fn extend_panic() { |
| panic!("ArrayVec: capacity exceeded in extend/from_iter"); |
| } |
| |
| impl<T, const CAP: usize> ArrayVec<T, CAP> { |
| /// Extend the arrayvec from the iterable. |
| /// |
| /// ## Safety |
| /// |
| /// Unsafe because if CHECK is false, the length of the input is not checked. |
| /// The caller must ensure the length of the input fits in the capacity. |
| #[track_caller] |
| pub(crate) unsafe fn extend_from_iter<I, const CHECK: bool>(&mut self, iterable: I) |
| where I: IntoIterator<Item = T> |
| { |
| let take = self.capacity() - self.len(); |
| let len = self.len(); |
| let mut ptr = raw_ptr_add(self.as_mut_ptr(), len); |
| let end_ptr = raw_ptr_add(ptr, take); |
| // Keep the length in a separate variable, write it back on scope |
| // exit. To help the compiler with alias analysis and stuff. |
| // We update the length to handle panic in the iteration of the |
| // user's iterator, without dropping any elements on the floor. |
| let mut guard = ScopeExitGuard { |
| value: &mut self.len, |
| data: len, |
| f: move |&len, self_len| { |
| **self_len = len as LenUint; |
| } |
| }; |
| let mut iter = iterable.into_iter(); |
| loop { |
| if let Some(elt) = iter.next() { |
| if ptr == end_ptr && CHECK { extend_panic(); } |
| debug_assert_ne!(ptr, end_ptr); |
| if mem::size_of::<T>() != 0 { |
| ptr.write(elt); |
| } |
| ptr = raw_ptr_add(ptr, 1); |
| guard.data += 1; |
| } else { |
| return; // success |
| } |
| } |
| } |
| |
| /// Extend the ArrayVec with clones of elements from the slice; |
| /// the length of the slice must be <= the remaining capacity in the arrayvec. |
| pub(crate) fn extend_from_slice(&mut self, slice: &[T]) |
| where T: Clone |
| { |
| let take = self.capacity() - self.len(); |
| debug_assert!(slice.len() <= take); |
| unsafe { |
| let slice = if take < slice.len() { &slice[..take] } else { slice }; |
| self.extend_from_iter::<_, false>(slice.iter().cloned()); |
| } |
| } |
| } |
| |
| /// Rawptr add but uses arithmetic distance for ZST |
| unsafe fn raw_ptr_add<T>(ptr: *mut T, offset: usize) -> *mut T { |
| if mem::size_of::<T>() == 0 { |
| // Special case for ZST |
| ptr.cast::<u8>().wrapping_add(offset).cast::<T>() |
| } else { |
| ptr.add(offset) |
| } |
| } |
| |
| /// Create an `ArrayVec` from an iterator. |
| /// |
| /// ***Panics*** if the number of elements in the iterator exceeds the arrayvec's capacity. |
| impl<T, const CAP: usize> iter::FromIterator<T> for ArrayVec<T, CAP> { |
| /// Create an `ArrayVec` from an iterator. |
| /// |
| /// ***Panics*** if the number of elements in the iterator exceeds the arrayvec's capacity. |
| fn from_iter<I: IntoIterator<Item=T>>(iter: I) -> Self { |
| let mut array = ArrayVec::new(); |
| array.extend(iter); |
| array |
| } |
| } |
| |
| impl<T, const CAP: usize> Clone for ArrayVec<T, CAP> |
| where T: Clone |
| { |
| fn clone(&self) -> Self { |
| self.iter().cloned().collect() |
| } |
| |
| fn clone_from(&mut self, rhs: &Self) { |
| // recursive case for the common prefix |
| let prefix = cmp::min(self.len(), rhs.len()); |
| self[..prefix].clone_from_slice(&rhs[..prefix]); |
| |
| if prefix < self.len() { |
| // rhs was shorter |
| self.truncate(prefix); |
| } else { |
| let rhs_elems = &rhs[self.len()..]; |
| self.extend_from_slice(rhs_elems); |
| } |
| } |
| } |
| |
| impl<T, const CAP: usize> Hash for ArrayVec<T, CAP> |
| where T: Hash |
| { |
| fn hash<H: Hasher>(&self, state: &mut H) { |
| Hash::hash(&**self, state) |
| } |
| } |
| |
| impl<T, const CAP: usize> PartialEq for ArrayVec<T, CAP> |
| where T: PartialEq |
| { |
| fn eq(&self, other: &Self) -> bool { |
| **self == **other |
| } |
| } |
| |
| impl<T, const CAP: usize> PartialEq<[T]> for ArrayVec<T, CAP> |
| where T: PartialEq |
| { |
| fn eq(&self, other: &[T]) -> bool { |
| **self == *other |
| } |
| } |
| |
| impl<T, const CAP: usize> Eq for ArrayVec<T, CAP> where T: Eq { } |
| |
| impl<T, const CAP: usize> Borrow<[T]> for ArrayVec<T, CAP> { |
| fn borrow(&self) -> &[T] { self } |
| } |
| |
| impl<T, const CAP: usize> BorrowMut<[T]> for ArrayVec<T, CAP> { |
| fn borrow_mut(&mut self) -> &mut [T] { self } |
| } |
| |
| impl<T, const CAP: usize> AsRef<[T]> for ArrayVec<T, CAP> { |
| fn as_ref(&self) -> &[T] { self } |
| } |
| |
| impl<T, const CAP: usize> AsMut<[T]> for ArrayVec<T, CAP> { |
| fn as_mut(&mut self) -> &mut [T] { self } |
| } |
| |
| impl<T, const CAP: usize> fmt::Debug for ArrayVec<T, CAP> where T: fmt::Debug { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { (**self).fmt(f) } |
| } |
| |
| impl<T, const CAP: usize> Default for ArrayVec<T, CAP> { |
| /// Return an empty array |
| fn default() -> ArrayVec<T, CAP> { |
| ArrayVec::new() |
| } |
| } |
| |
| impl<T, const CAP: usize> PartialOrd for ArrayVec<T, CAP> where T: PartialOrd { |
| fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> { |
| (**self).partial_cmp(other) |
| } |
| |
| fn lt(&self, other: &Self) -> bool { |
| (**self).lt(other) |
| } |
| |
| fn le(&self, other: &Self) -> bool { |
| (**self).le(other) |
| } |
| |
| fn ge(&self, other: &Self) -> bool { |
| (**self).ge(other) |
| } |
| |
| fn gt(&self, other: &Self) -> bool { |
| (**self).gt(other) |
| } |
| } |
| |
| impl<T, const CAP: usize> Ord for ArrayVec<T, CAP> where T: Ord { |
| fn cmp(&self, other: &Self) -> cmp::Ordering { |
| (**self).cmp(other) |
| } |
| } |
| |
| #[cfg(feature="std")] |
| /// `Write` appends written data to the end of the vector. |
| /// |
| /// Requires `features="std"`. |
| impl<const CAP: usize> io::Write for ArrayVec<u8, CAP> { |
| fn write(&mut self, data: &[u8]) -> io::Result<usize> { |
| let len = cmp::min(self.remaining_capacity(), data.len()); |
| let _result = self.try_extend_from_slice(&data[..len]); |
| debug_assert!(_result.is_ok()); |
| Ok(len) |
| } |
| fn flush(&mut self) -> io::Result<()> { Ok(()) } |
| } |
| |
| #[cfg(feature="serde")] |
| /// Requires crate feature `"serde"` |
| impl<T: Serialize, const CAP: usize> Serialize for ArrayVec<T, CAP> { |
| fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> |
| where S: Serializer |
| { |
| serializer.collect_seq(self) |
| } |
| } |
| |
| #[cfg(feature="serde")] |
| /// Requires crate feature `"serde"` |
| impl<'de, T: Deserialize<'de>, const CAP: usize> Deserialize<'de> for ArrayVec<T, CAP> { |
| fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> |
| where D: Deserializer<'de> |
| { |
| use serde::de::{Visitor, SeqAccess, Error}; |
| use std::marker::PhantomData; |
| |
| struct ArrayVecVisitor<'de, T: Deserialize<'de>, const CAP: usize>(PhantomData<(&'de (), [T; CAP])>); |
| |
| impl<'de, T: Deserialize<'de>, const CAP: usize> Visitor<'de> for ArrayVecVisitor<'de, T, CAP> { |
| type Value = ArrayVec<T, CAP>; |
| |
| fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { |
| write!(formatter, "an array with no more than {} items", CAP) |
| } |
| |
| fn visit_seq<SA>(self, mut seq: SA) -> Result<Self::Value, SA::Error> |
| where SA: SeqAccess<'de>, |
| { |
| let mut values = ArrayVec::<T, CAP>::new(); |
| |
| while let Some(value) = seq.next_element()? { |
| if let Err(_) = values.try_push(value) { |
| return Err(SA::Error::invalid_length(CAP + 1, &self)); |
| } |
| } |
| |
| Ok(values) |
| } |
| } |
| |
| deserializer.deserialize_seq(ArrayVecVisitor::<T, CAP>(PhantomData)) |
| } |
| } |
| |
| #[cfg(feature = "borsh")] |
| /// Requires crate feature `"borsh"` |
| impl<T, const CAP: usize> borsh::BorshSerialize for ArrayVec<T, CAP> |
| where |
| T: borsh::BorshSerialize, |
| { |
| fn serialize<W: borsh::io::Write>(&self, writer: &mut W) -> borsh::io::Result<()> { |
| <[T] as borsh::BorshSerialize>::serialize(self.as_slice(), writer) |
| } |
| } |
| |
| #[cfg(feature = "borsh")] |
| /// Requires crate feature `"borsh"` |
| impl<T, const CAP: usize> borsh::BorshDeserialize for ArrayVec<T, CAP> |
| where |
| T: borsh::BorshDeserialize, |
| { |
| fn deserialize_reader<R: borsh::io::Read>(reader: &mut R) -> borsh::io::Result<Self> { |
| let mut values = Self::new(); |
| let len = <u32 as borsh::BorshDeserialize>::deserialize_reader(reader)?; |
| for _ in 0..len { |
| let elem = <T as borsh::BorshDeserialize>::deserialize_reader(reader)?; |
| if let Err(_) = values.try_push(elem) { |
| return Err(borsh::io::Error::new( |
| borsh::io::ErrorKind::InvalidData, |
| format!("Expected an array with no more than {} items", CAP), |
| )); |
| } |
| } |
| |
| Ok(values) |
| } |
| } |
