/// Collection where an item can be inserted at a given index.
pub trait InsertIndex: cc_traits::Collection {
	type Output;

	fn insert_index(
		&mut self,
		index: usize,
		element: <Self as cc_traits::Collection>::Item,
	) -> Self::Output;
}

#[cfg(feature = "std")]
impl<T> InsertIndex for Vec<T> {
	type Output = ();

	fn insert_index(&mut self, index: usize, element: T) {
		self.insert(index, element)
	}
}

#[cfg(feature = "smallvec")]
impl<T, A: smallvec::Array<Item = T>> InsertIndex for smallvec::SmallVec<A> {
	type Output = ();

	fn insert_index(&mut self, index: usize, element: T) {
		self.insert(index, element)
	}
}