pub unsafe trait AsPtr: GetPointerKind {
// Required method
fn as_ptr(&self) -> *const Self::PtrTarget;
// Provided method
fn as_rref(&self) -> RRef<'_, Self::PtrTarget> { ... }
}Expand description
For getting a const raw pointer to the value that this points to.
§Safety
The implementor of this trait must return a pointer to the same data as
Deref::deref, without constructing a &Self::Target in as_ptr
(or any function it calls),
The implementor of this trait must not override the defaulted methods.
§Example
use abi_stable::{
erased_types::interfaces::DebugDefEqInterface,
pointer_trait::{
PK_Reference,
AsPtr, CanTransmuteElement, GetPointerKind, TransmuteElement,
},
sabi_types::StaticRef,
DynTrait,
};
fn main() {
let reff: DynTrait<BarRef<()>, DebugDefEqInterface> =
DynTrait::from_ptr(BarRef::new(&1234i32));
assert_eq!(format!("{:?}", reff), "1234");
}
#[derive(Debug, Copy, Clone)]
#[repr(transparent)]
struct BarRef<T>(StaticRef<T>);
impl<T: 'static> BarRef<T> {
pub const fn new(reff: &'static T) -> Self {
Self(StaticRef::new(reff))
}
}
unsafe impl<T: 'static> GetPointerKind for BarRef<T> {
type PtrTarget = T;
type Kind = PK_Reference;
}
unsafe impl<T, U> CanTransmuteElement<U> for BarRef<T>
where
T: 'static,
U: 'static,
{
type TransmutedPtr = BarRef<U>;
unsafe fn transmute_element_(self) -> Self::TransmutedPtr {
BarRef(self.0.transmute_element_())
}
}
unsafe impl<T: 'static> AsPtr for BarRef<T> {
fn as_ptr(&self) -> *const T {
self.0.as_ptr()
}
}
Required Methods§
Provided Methods§
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.