use std::fmt;
use std::iter::FusedIterator;
pub struct Keys<I> {
inner: I,
}
impl<I> Keys<I> {
pub(crate) fn new(inner: I) -> Self {
Self { inner }
}
}
impl<I: Clone> Clone for Keys<I> {
fn clone(&self) -> Self {
Self {
inner: self.inner.clone(),
}
}
}
impl<I, K, V> Iterator for Keys<I>
where
I: Iterator<Item = (K, V)>,
{
type Item = K;
#[inline]
fn next(&mut self) -> Option<K> {
self.inner.next().map(|(k, _)| k)
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
self.inner.size_hint()
}
#[inline]
fn fold<B, F: FnMut(B, K) -> B>(self, init: B, mut f: F) -> B {
self.inner.fold(init, move |acc, (k, _)| f(acc, k))
}
#[inline]
fn for_each<F: FnMut(K)>(self, mut f: F) {
self.inner.for_each(move |(k, _)| f(k));
}
}
impl<I, K, V> FusedIterator for Keys<I> where I: FusedIterator<Item = (K, V)> {}
impl<I> fmt::Debug for Keys<I> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Keys").finish_non_exhaustive()
}
}
pub struct Values<I> {
inner: I,
}
impl<I> Values<I> {
pub(crate) fn new(inner: I) -> Self {
Self { inner }
}
}
impl<I: Clone> Clone for Values<I> {
fn clone(&self) -> Self {
Self {
inner: self.inner.clone(),
}
}
}
impl<I, K, V> Iterator for Values<I>
where
I: Iterator<Item = (K, V)>,
{
type Item = V;
#[inline]
fn next(&mut self) -> Option<V> {
self.inner.next().map(|(_, v)| v)
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
self.inner.size_hint()
}
#[inline]
fn fold<B, F: FnMut(B, V) -> B>(self, init: B, mut f: F) -> B {
self.inner.fold(init, move |acc, (_, v)| f(acc, v))
}
#[inline]
fn for_each<F: FnMut(V)>(self, mut f: F) {
self.inner.for_each(move |(_, v)| f(v));
}
}
impl<I, K, V> FusedIterator for Values<I> where I: FusedIterator<Item = (K, V)> {}
impl<I> fmt::Debug for Values<I> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Values").finish_non_exhaustive()
}
}
pub struct IntoKeys<I> {
inner: I,
}
impl<I> IntoKeys<I> {
pub(crate) fn new(inner: I) -> Self {
Self { inner }
}
}
impl<I, K, V> Iterator for IntoKeys<I>
where
I: Iterator<Item = (K, V)>,
{
type Item = K;
#[inline]
fn next(&mut self) -> Option<K> {
self.inner.next().map(|(k, _)| k)
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
self.inner.size_hint()
}
#[inline]
fn fold<B, F: FnMut(B, K) -> B>(self, init: B, mut f: F) -> B {
self.inner.fold(init, move |acc, (k, _)| f(acc, k))
}
#[inline]
fn for_each<F: FnMut(K)>(self, mut f: F) {
self.inner.for_each(move |(k, _)| f(k));
}
}
impl<I, K, V> FusedIterator for IntoKeys<I> where I: FusedIterator<Item = (K, V)> {}
impl<I> fmt::Debug for IntoKeys<I> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("IntoKeys").finish_non_exhaustive()
}
}
pub struct IntoValues<I> {
inner: I,
}
impl<I> IntoValues<I> {
pub(crate) fn new(inner: I) -> Self {
Self { inner }
}
}
impl<I, K, V> Iterator for IntoValues<I>
where
I: Iterator<Item = (K, V)>,
{
type Item = V;
#[inline]
fn next(&mut self) -> Option<V> {
self.inner.next().map(|(_, v)| v)
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
self.inner.size_hint()
}
#[inline]
fn fold<B, F: FnMut(B, V) -> B>(self, init: B, mut f: F) -> B {
self.inner.fold(init, move |acc, (_, v)| f(acc, v))
}
#[inline]
fn for_each<F: FnMut(V)>(self, mut f: F) {
self.inner.for_each(move |(_, v)| f(v));
}
}
impl<I, K, V> FusedIterator for IntoValues<I> where I: FusedIterator<Item = (K, V)> {}
impl<I> fmt::Debug for IntoValues<I> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("IntoValues").finish_non_exhaustive()
}
}