//! Custom cell impl #[cfg(feature = "cell")] use std::cell::UnsafeCell; #[cfg(not(feature = "cell"))] use std::cell::{Ref, RefCell, RefMut}; use std::fmt; use std::rc::Rc; pub(crate) struct Cell<T> { #[cfg(feature = "cell")] inner: Rc<UnsafeCell<T>>, #[cfg(not(feature = "cell"))] inner: Rc<RefCell<T>>, } impl<T> Clone for Cell<T> { fn clone(&self) -> Self { Self { inner: self.inner.clone(), } } } impl<T: fmt::Debug> fmt::Debug for Cell<T> { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { self.inner.fmt(f) } } #[cfg(feature = "cell")] impl<T> Cell<T> { pub(crate) fn new(inner: T) -> Self { Self { inner: Rc::new(UnsafeCell::new(inner)), } } pub(crate) fn borrow(&self) -> &T { unsafe { &*self.inner.as_ref().get() } } pub(crate) fn borrow_mut(&self) -> &mut T { unsafe { &mut *self.inner.as_ref().get() } } } #[cfg(not(feature = "cell"))] impl<T> Cell<T> { pub(crate) fn new(inner: T) -> Self { Self { inner: Rc::new(RefCell::new(inner)), } } pub(crate) fn borrow(&self) -> Ref<T> { self.inner.borrow() } pub(crate) fn borrow_mut(&self) -> RefMut<T> { self.inner.borrow_mut() } }