use std::fmt;
use std::any::Any as StdAny;
#[doc(hidden)]
pub trait CloneToAny {
fn clone_to_any(&self) -> Box<CloneAny>;
fn clone_to_any_send(&self) -> Box<CloneAny + Send> where Self: Send;
fn clone_to_any_sync(&self) -> Box<CloneAny + Sync> where Self: Sync;
fn clone_to_any_send_sync(&self) -> Box<CloneAny + Send + Sync> where Self: Send + Sync;
}
impl<T: Any + Clone> CloneToAny for T {
#[inline]
fn clone_to_any(&self) -> Box<CloneAny> {
Box::new(self.clone())
}
#[inline]
fn clone_to_any_send(&self) -> Box<CloneAny + Send> where Self: Send {
Box::new(self.clone())
}
#[inline]
fn clone_to_any_sync(&self) -> Box<CloneAny + Sync> where Self: Sync {
Box::new(self.clone())
}
#[inline]
fn clone_to_any_send_sync(&self) -> Box<CloneAny + Send + Sync> where Self: Send + Sync {
Box::new(self.clone())
}
}
macro_rules! define {
(CloneAny) => {
define!(CloneAny remainder);
};
(Any) => {
define!(Any remainder);
};
($t:ident remainder) => {
define!($t trait);
};
(CloneAny trait) => {
pub trait CloneAny: Any + CloneToAny { }
impl<T: StdAny + Clone> CloneAny for T { }
};
(Any trait) => {
pub trait Any: StdAny { }
impl<T: StdAny> Any for T { }
};
}
macro_rules! impl_clone {
($t:ty, $method:ident) => {
impl Clone for Box<$t> {
#[inline]
fn clone(&self) -> Box<$t> {
(**self).$method()
}
}
}
}
#[allow(missing_docs)] pub trait UncheckedAnyExt: Any {
unsafe fn downcast_ref_unchecked<T: Any>(&self) -> &T;
unsafe fn downcast_mut_unchecked<T: Any>(&mut self) -> &mut T;
unsafe fn downcast_unchecked<T: Any>(self: Box<Self>) -> Box<T>;
}
#[doc(hidden)]
pub trait IntoBox<A: ?Sized + UncheckedAnyExt>: Any {
fn into_box(self) -> Box<A>;
}
macro_rules! implement {
($base:ident, $(+ $bounds:ident)*) => {
impl fmt::Debug for $base $(+ $bounds)* {
#[inline]
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.pad(stringify!($base $(+ $bounds)*))
}
}
impl UncheckedAnyExt for $base $(+ $bounds)* {
#[inline]
unsafe fn downcast_ref_unchecked<T: 'static>(&self) -> &T {
&*(self as *const Self as *const T)
}
#[inline]
unsafe fn downcast_mut_unchecked<T: 'static>(&mut self) -> &mut T {
&mut *(self as *mut Self as *mut T)
}
#[inline]
unsafe fn downcast_unchecked<T: 'static>(self: Box<Self>) -> Box<T> {
Box::from_raw(Box::into_raw(self) as *mut T)
}
}
impl<T: $base $(+ $bounds)*> IntoBox<$base $(+ $bounds)*> for T {
#[inline]
fn into_box(self) -> Box<$base $(+ $bounds)*> {
Box::new(self)
}
}
}
}
define!(Any);
implement!(Any,);
implement!(Any, + Send);
implement!(Any, + Sync);
implement!(Any, + Send + Sync);
implement!(CloneAny,);
implement!(CloneAny, + Send);
implement!(CloneAny, + Sync);
implement!(CloneAny, + Send + Sync);
define!(CloneAny);
impl_clone!(CloneAny, clone_to_any);
impl_clone!((CloneAny + Send), clone_to_any_send);
impl_clone!((CloneAny + Sync), clone_to_any_sync);
impl_clone!((CloneAny + Send + Sync), clone_to_any_send_sync);