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    #![allow(unused_variables)]
    #![allow(missing_docs)]

    use super::*;

    /// A slice-backed vector-like data structure.
    ///
    /// This is a very similar concept to `ArrayVec`, but instead
    /// of the backing memory being an owned array, the backing
    /// memory is a unique-borrowed slice. You can thus create
    /// one of these structures "around" some slice that you're
    /// working with to make it easier to manipulate.
    ///
    /// * Has a fixed capacity (the initial slice size).
    /// * Has a variable length.
    pub struct SliceVec<'s, T> {
      data: &'s mut [T],
      len: usize,
    }

    impl<'s, T> Default for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn default() -> Self {
        Self { data: &mut [], len: 0 }
      }
    }

    impl<'s, T> Deref for SliceVec<'s, T> {
      type Target = [T];
      #[inline(always)]
      #[must_use]
      fn deref(&self) -> &Self::Target {
        &self.data[..self.len]
      }
    }

    impl<'s, T> DerefMut for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.data[..self.len]
      }
    }

    impl<'s, T, I> Index<I> for SliceVec<'s, T>
    where
      I: SliceIndex<[T]>,
    {
      type Output = <I as SliceIndex<[T]>>::Output;
      #[inline(always)]
      #[must_use]
      fn index(&self, index: I) -> &Self::Output {
        &self.deref()[index]
      }
    }

    impl<'s, T, I> IndexMut<I> for SliceVec<'s, T>
    where
      I: SliceIndex<[T]>,
    {
      #[inline(always)]
      #[must_use]
      fn index_mut(&mut self, index: I) -> &mut Self::Output {
        &mut self.deref_mut()[index]
      }
    }

    impl<'s, T> SliceVec<'s, T> {
      #[inline]
      pub fn append(&mut self, other: &mut Self)
      where
        T: Default,
      {
        for item in other.drain(..) {
          self.push(item)
        }
      }

      /// A `*mut` pointer to the backing slice.
      ///
      /// ## Safety
      ///
      /// This pointer has provenance over the _entire_ backing slice.
      #[inline(always)]
      #[must_use]
      pub fn as_mut_ptr(&mut self) -> *mut T {
        self.data.as_mut_ptr()
      }

      /// Performs a `deref_mut`, into unique slice form.
      #[inline(always)]
      #[must_use]
      pub fn as_mut_slice(&mut self) -> &mut [T] {
        self.deref_mut()
      }

      /// A `*const` pointer to the backing slice.
      ///
      /// ## Safety
      ///
      /// This pointer has provenance over the _entire_ backing slice.
      #[inline(always)]
      #[must_use]
      pub fn as_ptr(&self) -> *const T {
        self.data.as_ptr()
      }

      /// Performs a `deref`, into shared slice form.
      #[inline(always)]
      #[must_use]
      pub fn as_slice(&self) -> &[T] {
        self.deref()
      }

      /// The capacity of the `SliceVec`.
      ///
      /// This the length of the initial backing slice.
      #[inline(always)]
      #[must_use]
      pub fn capacity(&self) -> usize {
        self.data.len()
      }

      /// Truncates the `SliceVec` down to length 0.
      #[inline(always)]
      pub fn clear(&mut self)
      where
        T: Default,
      {
        self.truncate(0)
      }

      /// Creates a draining iterator that removes the specified range in the vector
      /// and yields the removed items.
      ///
      /// ## Panics
      /// * If the start is greater than the end
      /// * If the end is past the edge of the vec.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [6, 7, 8];
      /// let mut sv = SliceVec::from(&mut arr);
      /// let drained_values: ArrayVec<[i32; 4]> = sv.drain(1..).collect();
      /// assert_eq!(sv.as_slice(), &[6][..]);
      /// assert_eq!(drained_values.as_slice(), &[7, 8][..]);
      ///
      /// sv.drain(..);
      /// assert_eq!(sv.as_slice(), &[]);
      /// ```
      #[inline]
      pub fn drain<'p, R: RangeBounds<usize>>(
        &'p mut self, range: R,
      ) -> SliceVecDrain<'p, 's, T>
      where
        T: Default,
      {
        use core::ops::Bound;
        let start = match range.start_bound() {
          Bound::Included(x) => *x,
          Bound::Excluded(x) => x.saturating_add(1),
          Bound::Unbounded => 0,
        };
        let end = match range.end_bound() {
          Bound::Included(x) => x.saturating_add(1),
          Bound::Excluded(x) => *x,
          Bound::Unbounded => self.len,
        };
        assert!(
          start <= end,
          "SliceVec::drain> Illegal range, {} to {}",
          start,
          end
        );
        assert!(
          end <= self.len,
          "SliceVec::drain> Range ends at {} but length is only {}!",
          end,
          self.len
        );
        SliceVecDrain {
          parent: self,
          target_start: start,
          target_index: start,
          target_end: end,
        }
      }

      #[inline]
      pub fn extend_from_slice(&mut self, sli: &[T])
      where
        T: Clone,
      {
        if sli.is_empty() {
          return;
        }

        let new_len = self.len + sli.len();
        if new_len > self.capacity() {
          panic!(
            "SliceVec::extend_from_slice> total length {} exceeds capacity {}",
            new_len,
            self.capacity()
          )
        }

        let target = &mut self.data[self.len..new_len];
        target.clone_from_slice(sli);
        self.set_len(new_len);
      }

      /// Fill the vector until its capacity has been reached.
      ///
      /// Successively fills unused space in the spare slice of the vector with
      /// elements from the iterator. It then returns the remaining iterator
      /// without exhausting it. This also allows appending the head of an
      /// infinite iterator.
      ///
      /// This is an alternative to `Extend::extend` method for cases where the
      /// length of the iterator can not be checked. Since this vector can not
      /// reallocate to increase its capacity, it is unclear what to do with
      /// remaining elements in the iterator and the iterator itself. The
      /// interface also provides no way to communicate this to the caller.
      ///
      /// ## Panics
      /// * If the `next` method of the provided iterator panics.
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [7, 7, 7, 7];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 0);
      /// let mut to_inf = sv.fill(0..);
      /// assert_eq!(&sv[..], [0, 1, 2, 3]);
      /// assert_eq!(to_inf.next(), Some(4));
      /// ```
      #[inline]
      pub fn fill<I: IntoIterator<Item = T>>(&mut self, iter: I) -> I::IntoIter {
        let mut iter = iter.into_iter();
        for element in iter.by_ref().take(self.capacity() - self.len()) {
          self.push(element);
        }
        iter
      }

      /// Wraps up a slice and uses the given length as the initial length.
      ///
      /// If you want to simply use the full slice, use `from` instead.
      ///
      /// ## Panics
      ///
      /// * The length specified must be less than or equal to the capacity of the
      ///   slice.
      #[inline]
      #[must_use]
      #[allow(clippy::match_wild_err_arm)]
      pub fn from_slice_len(data: &'s mut [T], len: usize) -> Self {
        assert!(len <= data.len());
        Self { data, len }
      }

      /// Inserts an item at the position given, moving all following elements +1
      /// index.
      ///
      /// ## Panics
      /// * If `index` > `len`
      /// * If the capacity is exhausted
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [1, 2, 3, 0, 0];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 3);
      /// sv.insert(1, 4);
      /// assert_eq!(sv.as_slice(), &[1, 4, 2, 3]);
      /// sv.insert(4, 5);
      /// assert_eq!(sv.as_slice(), &[1, 4, 2, 3, 5]);
      /// ```
      #[inline]
      pub fn insert(&mut self, index: usize, item: T) {
        if index > self.len {
          panic!("SliceVec::insert> index {} is out of bounds {}", index, self.len);
        }

        // Try to push the element.
        self.push(item);
        // And move it into its place.
        self.as_mut_slice()[index..].rotate_right(1);
      }

      /// Checks if the length is 0.
      #[inline(always)]
      #[must_use]
      pub fn is_empty(&self) -> bool {
        self.len == 0
      }

      /// The length of the `SliceVec` (in elements).
      #[inline(always)]
      #[must_use]
      pub fn len(&self) -> usize {
        self.len
      }

      /// Remove and return the last element of the vec, if there is one.
      ///
      /// ## Failure
      /// * If the vec is empty you get `None`.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [1, 2];
      /// let mut sv = SliceVec::from(&mut arr);
      /// assert_eq!(sv.pop(), Some(2));
      /// assert_eq!(sv.pop(), Some(1));
      /// assert_eq!(sv.pop(), None);
      /// ```
      #[inline]
      pub fn pop(&mut self) -> Option<T>
      where
        T: Default,
      {
        if self.len > 0 {
          self.len -= 1;
          let out = take(&mut self.data[self.len]);
          Some(out)
        } else {
          None
        }
      }

      /// Place an element onto the end of the vec.
      ///
      /// ## Panics
      /// * If the length of the vec would overflow the capacity.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [0, 0];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 0);
      /// assert_eq!(&sv[..], []);
      /// sv.push(1);
      /// assert_eq!(&sv[..], [1]);
      /// sv.push(2);
      /// assert_eq!(&sv[..], [1, 2]);
      /// // sv.push(3); this would overflow the ArrayVec and panic!
      /// ```
      #[inline(always)]
      pub fn push(&mut self, val: T) {
        if self.len < self.capacity() {
          self.data[self.len] = val;
          self.len += 1;
        } else {
          panic!("SliceVec::push> capacity overflow")
        }
      }

      /// Removes the item at `index`, shifting all others down by one index.
      ///
      /// Returns the removed element.
      ///
      /// ## Panics
      ///
      /// * If the index is out of bounds.
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [1, 2, 3];
      /// let mut sv = SliceVec::from(&mut arr);
      /// assert_eq!(sv.remove(1), 2);
      /// assert_eq!(&sv[..], [1, 3]);
      /// ```
      #[inline]
      pub fn remove(&mut self, index: usize) -> T
      where
        T: Default,
      {
        let targets: &mut [T] = &mut self.deref_mut()[index..];
        let item = take(&mut targets[0]);
        targets.rotate_left(1);
        self.len -= 1;
        item
      }

      /// As [`resize_with`](SliceVec::resize_with)
      /// and it clones the value as the closure.
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      /// // bigger
      /// let mut arr = ["hello", "", "", "", ""];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 1);
      /// sv.resize(3, "world");
      /// assert_eq!(&sv[..], ["hello", "world", "world"]);
      ///
      /// // smaller
      /// let mut arr = ['a', 'b', 'c', 'd'];
      /// let mut sv = SliceVec::from(&mut arr);
      /// sv.resize(2, 'z');
      /// assert_eq!(&sv[..], ['a', 'b']);
      /// ```
      #[inline]
      pub fn resize(&mut self, new_len: usize, new_val: T)
      where
        T: Clone,
      {
        self.resize_with(new_len, || new_val.clone())
      }

      /// Resize the vec to the new length.
      ///
      /// * If it needs to be longer, it's filled with repeated calls to the
      ///   provided function.
      /// * If it needs to be shorter, it's truncated.
      ///   * If the type needs to drop the truncated slots are filled with calls to
      ///     the provided function.
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [1, 2, 3, 7, 7, 7, 7];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 3);
      /// sv.resize_with(5, Default::default);
      /// assert_eq!(&sv[..], [1, 2, 3, 0, 0]);
      ///
      /// let mut arr = [0, 0, 0, 0];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 0);
      /// let mut p = 1;
      /// sv.resize_with(4, || {
      ///   p *= 2;
      ///   p
      /// });
      /// assert_eq!(&sv[..], [2, 4, 8, 16]);
      /// ```
      #[inline]
      pub fn resize_with<F: FnMut() -> T>(&mut self, new_len: usize, mut f: F) {
        match new_len.checked_sub(self.len) {
          None => {
            if needs_drop::<T>() {
              while self.len() > new_len {
                self.len -= 1;
                self.data[self.len] = f();
              }
            } else {
              self.len = new_len;
            }
          }
          Some(new_elements) => {
            for _ in 0..new_elements {
              self.push(f());
            }
          }
        }
      }

      /// Walk the vec and keep only the elements that pass the predicate given.
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      ///
      /// let mut arr = [1, 1, 2, 3, 3, 4];
      /// let mut sv = SliceVec::from(&mut arr);
      /// sv.retain(|&x| x % 2 == 0);
      /// assert_eq!(&sv[..], [2, 4]);
      /// ```
      #[inline]
      pub fn retain<F: FnMut(&T) -> bool>(&mut self, mut acceptable: F)
      where
        T: Default,
      {
        // Drop guard to contain exactly the remaining elements when the test
        // panics.
        struct JoinOnDrop<'vec, Item> {
          items: &'vec mut [Item],
          done_end: usize,
          // Start of tail relative to `done_end`.
          tail_start: usize,
        }

        impl<Item> Drop for JoinOnDrop<'_, Item> {
          fn drop(&mut self) {
            self.items[self.done_end..].rotate_left(self.tail_start);
          }
        }

        let mut rest = JoinOnDrop { items: self.data, done_end: 0, tail_start: 0 };

        for idx in 0..self.len {
          // Loop start invariant: idx = rest.done_end + rest.tail_start
          if !acceptable(&rest.items[idx]) {
            let _ = take(&mut rest.items[idx]);
            self.len -= 1;
            rest.tail_start += 1;
          } else {
            rest.items.swap(rest.done_end, idx);
            rest.done_end += 1;
          }
        }
      }

      /// Forces the length of the vector to `new_len`.
      ///
      /// ## Panics
      /// * If `new_len` is greater than the vec's capacity.
      ///
      /// ## Safety
      /// * This is a fully safe operation! The inactive memory already counts as
      ///   "initialized" by Rust's rules.
      /// * Other than "the memory is initialized" there are no other guarantees
      ///   regarding what you find in the inactive portion of the vec.
      #[inline(always)]
      pub fn set_len(&mut self, new_len: usize) {
        if new_len > self.capacity() {
          // Note(Lokathor): Technically we don't have to panic here, and we could
          // just let some other call later on trigger a panic on accident when the
          // length is wrong. However, it's a lot easier to catch bugs when things
          // are more "fail-fast".
          panic!(
            "SliceVec::set_len> new length {} exceeds capacity {}",
            new_len,
            self.capacity()
          )
        } else {
          self.len = new_len;
        }
      }

      /// Splits the collection at the point given.
      ///
      /// * `[0, at)` stays in this vec (and this vec is now full).
      /// * `[at, len)` ends up in the new vec (with any spare capacity).
      ///
      /// ## Panics
      /// * if `at` > `self.len()`
      ///
      /// ## Example
      ///
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [1, 2, 3];
      /// let mut sv = SliceVec::from(&mut arr);
      /// let sv2 = sv.split_off(1);
      /// assert_eq!(&sv[..], [1]);
      /// assert_eq!(&sv2[..], [2, 3]);
      /// ```
      #[inline]
      pub fn split_off<'a>(&'a mut self, at: usize) -> SliceVec<'s, T> {
        let mut new = Self::default();
        let backing: &'s mut [T] = replace(&mut self.data, &mut []);
        let (me, other) = backing.split_at_mut(at);
        new.len = self.len - at;
        new.data = other;
        self.len = me.len();
        self.data = me;
        new
      }

      /// Remove an element, swapping the end of the vec into its place.
      ///
      /// ## Panics
      /// * If the index is out of bounds.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = ["foo", "bar", "quack", "zap"];
      /// let mut sv = SliceVec::from(&mut arr);
      ///
      /// assert_eq!(sv.swap_remove(1), "bar");
      /// assert_eq!(&sv[..], ["foo", "zap", "quack"]);
      ///
      /// assert_eq!(sv.swap_remove(0), "foo");
      /// assert_eq!(&sv[..], ["quack", "zap"]);
      /// ```
      #[inline]
      pub fn swap_remove(&mut self, index: usize) -> T
      where
        T: Default,
      {
        assert!(
          index < self.len,
          "SliceVec::swap_remove> index {} is out of bounds {}",
          index,
          self.len
        );
        if index == self.len - 1 {
          self.pop().unwrap()
        } else {
          let i = self.pop().unwrap();
          replace(&mut self[index], i)
        }
      }

      /// Reduces the vec's length to the given value.
      ///
      /// If the vec is already shorter than the input, nothing happens.
      #[inline]
      pub fn truncate(&mut self, new_len: usize)
      where
        T: Default,
      {
        if needs_drop::<T>() {
          while self.len > new_len {
            self.pop();
          }
        } else {
          self.len = self.len.min(new_len);
        }
      }

      /// Wraps a slice, using the given length as the starting length.
      ///
      /// If you want to use the whole length of the slice, you can just use the
      /// `From` impl.
      ///
      /// ## Failure
      ///
      /// If the given length is greater than the length of the slice you get
      /// `None`.
      #[inline]
      pub fn try_from_slice_len(data: &'s mut [T], len: usize) -> Option<Self> {
        if len <= data.len() {
          Some(Self { data, len })
        } else {
          None
        }
      }
    }

    #[cfg(feature = "grab_spare_slice")]
    impl<'s, T> SliceVec<'s, T> {
      /// Obtain the shared slice of the array _after_ the active memory.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [0; 4];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 0);
      /// assert_eq!(sv.grab_spare_slice().len(), 4);
      /// sv.push(10);
      /// sv.push(11);
      /// sv.push(12);
      /// sv.push(13);
      /// assert_eq!(sv.grab_spare_slice().len(), 0);
      /// ```
      #[inline(always)]
      pub fn grab_spare_slice(&self) -> &[T] {
        &self.data[self.len..]
      }

      /// Obtain the mutable slice of the array _after_ the active memory.
      ///
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [0; 4];
      /// let mut sv = SliceVec::from_slice_len(&mut arr, 0);
      /// assert_eq!(sv.grab_spare_slice_mut().len(), 4);
      /// sv.push(10);
      /// sv.push(11);
      /// assert_eq!(sv.grab_spare_slice_mut().len(), 2);
      /// ```
      #[inline(always)]
      pub fn grab_spare_slice_mut(&mut self) -> &mut [T] {
        &mut self.data[self.len..]
      }
    }

    impl<'s, T> From<&'s mut [T]> for SliceVec<'s, T> {
      /// Uses the full slice as the initial length.
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [0_i32; 2];
      /// let mut sv = SliceVec::from(&mut arr[..]);
      /// ```
      fn from(data: &'s mut [T]) -> Self {
        let len = data.len();
        Self { data, len }
      }
    }

    impl<'s, T, A> From<&'s mut A> for SliceVec<'s, T>
    where
      A: AsMut<[T]>,
    {
      /// Calls `AsRef::as_mut` then uses the full slice as the initial length.
      /// ## Example
      /// ```rust
      /// # use tinyvec::*;
      /// let mut arr = [0, 0];
      /// let mut sv = SliceVec::from(&mut arr);
      /// ```
      fn from(a: &'s mut A) -> Self {
        let data = a.as_mut();
        let len = data.len();
        Self { data, len }
      }
    }

    /// Draining iterator for [`SliceVec`]
    ///
    /// See [`SliceVec::drain`](SliceVec::drain)
    pub struct SliceVecDrain<'p, 's, T: Default> {
      parent: &'p mut SliceVec<'s, T>,
      target_start: usize,
      target_index: usize,
      target_end: usize,
    }
    impl<'p, 's, T: Default> Iterator for SliceVecDrain<'p, 's, T> {
      type Item = T;
      #[inline]
      fn next(&mut self) -> Option<Self::Item> {
        if self.target_index != self.target_end {
          let out = take(&mut self.parent[self.target_index]);
          self.target_index += 1;
          Some(out)
        } else {
          None
        }
      }
    }
    impl<'p, 's, T: Default> FusedIterator for SliceVecDrain<'p, 's, T> {}
    impl<'p, 's, T: Default> Drop for SliceVecDrain<'p, 's, T> {
      #[inline]
      fn drop(&mut self) {
        // Changed because it was moving `self`, it's also more clear and the std
        // does the same
        self.for_each(drop);
        // Implementation very similar to [`SliceVec::remove`](SliceVec::remove)
        let count = self.target_end - self.target_start;
        let targets: &mut [T] = &mut self.parent.deref_mut()[self.target_start..];
        targets.rotate_left(count);
        self.parent.len -= count;
      }
    }

    impl<'s, T> AsMut<[T]> for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn as_mut(&mut self) -> &mut [T] {
        &mut *self
      }
    }

    impl<'s, T> AsRef<[T]> for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn as_ref(&self) -> &[T] {
        &*self
      }
    }

    impl<'s, T> Borrow<[T]> for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn borrow(&self) -> &[T] {
        &*self
      }
    }

    impl<'s, T> BorrowMut<[T]> for SliceVec<'s, T> {
      #[inline(always)]
      #[must_use]
      fn borrow_mut(&mut self) -> &mut [T] {
        &mut *self
      }
    }

    impl<'s, T> Extend<T> for SliceVec<'s, T> {
      #[inline]
      fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) {
        for t in iter {
          self.push(t)
        }
      }
    }

    impl<'s, T> IntoIterator for SliceVec<'s, T> {
      type Item = &'s mut T;
      type IntoIter = core::slice::IterMut<'s, T>;
      #[inline(always)]
      #[must_use]
      fn into_iter(self) -> Self::IntoIter {
        self.data.iter_mut()
      }
    }

    impl<'s, T> PartialEq for SliceVec<'s, T>
    where
      T: PartialEq,
    {
      #[inline]
      #[must_use]
      fn eq(&self, other: &Self) -> bool {
        self.as_slice().eq(other.as_slice())
      }
    }
    impl<'s, T> Eq for SliceVec<'s, T> where T: Eq {}

    impl<'s, T> PartialOrd for SliceVec<'s, T>
    where
      T: PartialOrd,
    {
      #[inline]
      #[must_use]
      fn partial_cmp(&self, other: &Self) -> Option<core::cmp::Ordering> {
        self.as_slice().partial_cmp(other.as_slice())
      }
    }
    impl<'s, T> Ord for SliceVec<'s, T>
    where
      T: Ord,
    {
      #[inline]
      #[must_use]
      fn cmp(&self, other: &Self) -> core::cmp::Ordering {
        self.as_slice().cmp(other.as_slice())
      }
    }

    impl<'s, T> PartialEq<&[T]> for SliceVec<'s, T>
    where
      T: PartialEq,
    {
      #[inline]
      #[must_use]
      fn eq(&self, other: &&[T]) -> bool {
        self.as_slice().eq(*other)
      }
    }

    impl<'s, T> Hash for SliceVec<'s, T>
    where
      T: Hash,
    {
      #[inline]
      fn hash<H: Hasher>(&self, state: &mut H) {
        self.as_slice().hash(state)
      }
    }

    #[cfg(feature = "experimental_write_impl")]
    impl<'s> core::fmt::Write for SliceVec<'s, u8> {
      fn write_str(&mut self, s: &str) -> core::fmt::Result {
        let my_len = self.len();
        let str_len = s.as_bytes().len();
        if my_len + str_len <= self.capacity() {
          let remainder = &mut self.data[my_len..];
          let target = &mut remainder[..str_len];
          target.copy_from_slice(s.as_bytes());
          Ok(())
        } else {
          Err(core::fmt::Error)
        }
      }
    }

    // // // // // // // //
    // Formatting impls
    // // // // // // // //

    impl<'s, T> Binary for SliceVec<'s, T>
    where
      T: Binary,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          Binary::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> Debug for SliceVec<'s, T>
    where
      T: Debug,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          Debug::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> Display for SliceVec<'s, T>
    where
      T: Display,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          Display::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> LowerExp for SliceVec<'s, T>
    where
      T: LowerExp,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          LowerExp::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> LowerHex for SliceVec<'s, T>
    where
      T: LowerHex,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          LowerHex::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> Octal for SliceVec<'s, T>
    where
      T: Octal,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          Octal::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> Pointer for SliceVec<'s, T>
    where
      T: Pointer,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          Pointer::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> UpperExp for SliceVec<'s, T>
    where
      T: UpperExp,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          UpperExp::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }

    impl<'s, T> UpperHex for SliceVec<'s, T>
    where
      T: UpperHex,
    {
      #[allow(clippy::missing_inline_in_public_items)]
      fn fmt(&self, f: &mut Formatter) -> core::fmt::Result {
        write!(f, "[")?;
        for (i, elem) in self.iter().enumerate() {
          if i > 0 {
            write!(f, ", ")?;
          }
          UpperHex::fmt(elem, f)?;
        }
        write!(f, "]")
      }
    }