#[cfg(feature = "alloc")]
use alloc::{
collections::{BTreeMap, BTreeSet},
string::String,
vec::Vec,
};
#[cfg(feature = "std")]
use std::collections::{HashMap, HashSet};
use crate::SingleItemStorage;
pub trait Length {
fn length(&self) -> usize;
}
impl<T> Length for &T
where
T: Length,
{
#[inline]
fn length(&self) -> usize {
(*self).length()
}
}
impl Length for () {
#[inline]
fn length(&self) -> usize {
0
}
}
impl<T> Length for Option<T> {
#[inline]
fn length(&self) -> usize {
usize::from(self.is_some())
}
}
impl<T> Length for SingleItemStorage<T> {
#[inline]
fn length(&self) -> usize {
1
}
}
impl<T> Length for &'_ [T] {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
impl<T> Length for &'_ mut [T] {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
impl<T, const N: usize> Length for [T; N] {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "alloc")]
impl<K, V> Length for BTreeMap<K, V> {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "alloc")]
impl<V> Length for BTreeSet<V> {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "std")]
impl<K, V, S> Length for HashMap<K, V, S>
where
S: core::hash::BuildHasher,
{
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "std")]
impl<V, S> Length for HashSet<V, S>
where
S: core::hash::BuildHasher,
{
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "alloc")]
impl Length for String {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "alloc")]
impl<T> Length for Vec<T> {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "arrayvec")]
impl<const N: usize> Length for arrayvec::ArrayString<N> {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "arrayvec")]
impl<T, const N: usize> Length for arrayvec::ArrayVec<T, N> {
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "smallvec")]
impl<A> Length for smallvec::SmallVec<A>
where
A: smallvec::Array,
{
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(feature = "tinyvec")]
impl<A> Length for tinyvec::ArrayVec<A>
where
A: tinyvec::Array,
A::Item: Default,
{
#[inline]
fn length(&self) -> usize {
self.len()
}
}
#[cfg(all(feature = "alloc", feature = "tinyvec"))]
impl<A> Length for tinyvec::TinyVec<A>
where
A: tinyvec::Array,
A::Item: Default,
{
#[inline]
fn length(&self) -> usize {
self.len()
}
}