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use std::borrow::Borrow;
use std::cell::RefMut;
use std::fmt;
use std::ops::Deref;
use std::ops::DerefMut;
pub enum XRefMut<'a, T> {
Borrowed(&'a mut T),
Ref(RefMut<'a, T>),
Owned(T),
}
impl<'a, T> XRefMut<'a, T> {
pub fn to_ref(&self) -> &T {
match self {
Self::Borrowed(r) => r,
Self::Ref(r) => r,
Self::Owned(t) => t,
}
}
pub fn to_mut(&mut self) -> &mut T {
match self {
Self::Borrowed(r) => r,
Self::Ref(r) => r,
Self::Owned(ref mut t) => t,
}
}
}
impl<'a, T: Clone> XRefMut<'a, T> {
pub fn into_owned(self) -> T {
match self {
Self::Borrowed(r) => r.clone(),
Self::Ref(r) => r.clone(),
Self::Owned(t) => t,
}
}
}
impl<'a, T> AsRef<T> for XRefMut<'a, T> {
fn as_ref(&self) -> &T {
match self {
Self::Borrowed(r) => r,
Self::Ref(r) => r,
Self::Owned(t) => t.borrow(),
}
}
}
impl<'a, T> Borrow<T> for XRefMut<'a, T> {
fn borrow(&self) -> &T {
&**self
}
}
impl<'a, T: fmt::Debug> fmt::Debug for XRefMut<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Borrowed(r) => fmt::Debug::fmt(r, f),
Self::Ref(r) => fmt::Debug::fmt(r, f),
Self::Owned(t) => fmt::Debug::fmt(t, f),
}
}
}
impl<'a, T: fmt::Display> fmt::Display for XRefMut<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Borrowed(r) => fmt::Display::fmt(r, f),
Self::Ref(r) => fmt::Display::fmt(r, f),
Self::Owned(t) => fmt::Display::fmt(t, f),
}
}
}
impl<'a, T: Default> Default for XRefMut<'a, T> {
fn default() -> Self {
Self::Owned(Default::default())
}
}
impl<'a, T> Deref for XRefMut<'a, T> {
type Target = T;
fn deref(&self) -> &T {
self.to_ref()
}
}
impl<'a, T> DerefMut for XRefMut<'a, T> {
fn deref_mut(&mut self) -> &mut T {
self.to_mut()
}
}