Trait thin::DynSized

pub unsafe trait DynSized {
    type Meta: Copy;
    fn assemble(meta: Self::Meta, data: *const ()) -> *const Self;
    fn disassemble(ptr: *const Self) -> (Self::Meta, *const ());

    fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self { ... }
    fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ()) { ... }
    fn meta(&self) -> Self::Meta { ... }
    fn data(&self) -> *const () { ... }
    fn data_mut(&mut self) -> *mut () { ... }
}

A trait for dynamically sized types, similar in principle to the Sized trait. Allows conversion between fat and thin pointers.

The assemble and disassemble methods must be safe, i.e. they must not dereference the raw pointers, only use them to extract the metadata in the case of disassemble, or to combine with metadata to produce a fat pointer, in the case of assemble.

Unsafety

The trait is marked unsafe, because implementing it wrong can cause undefined behaviour.

Associated Types

type Meta: Copy

Required Methods

fn assemble(meta: Self::Meta, data: *const ()) -> *const Self

fn disassemble(ptr: *const Self) -> (Self::Meta, *const ())

Provided Methods

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

Implementations on Foreign Types

impl<'a, Args, Output> DynSized for FnMut<Args, Output = Output> + 'a + Send

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const FnMut<Args, Output = Output> + 'a + Send

fn disassemble(
    ptr: *const FnMut<Args, Output = Output> + 'a + Send
) -> (<FnMut<Args, Output = Output> + 'a + Send as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for FnMut<Args, Output = Output> + 'a

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const FnMut<Args, Output = Output> + 'a

fn disassemble(
    ptr: *const FnMut<Args, Output = Output> + 'a
) -> (<FnMut<Args, Output = Output> + 'a as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl DynSized for Any + 'static

type Meta = Vtable

fn assemble(vtable: Vtable, data: *const ()) -> *const Any + 'static

fn disassemble(
    ptr: *const Any + 'static
) -> (<Any + 'static as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<T> DynSized for [T]

type Meta = usize

fn assemble(len: usize, data: *const ()) -> *const [T]

fn disassemble(slice: *const [T]) -> (usize, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for Fn<Args, Output = Output> + 'a + Send + Sync

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const Fn<Args, Output = Output> + 'a + Send + Sync

fn disassemble(
    ptr: *const Fn<Args, Output = Output> + 'a + Send + Sync
) -> (<Fn<Args, Output = Output> + 'a + Send + Sync as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl DynSized for str

type Meta = usize

fn assemble(len: usize, data: *const ()) -> *const str

fn disassemble(s: *const str) -> (usize, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for FnOnce<Args, Output = Output> + 'a + Send

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const FnOnce<Args, Output = Output> + 'a + Send

fn disassemble(
    ptr: *const FnOnce<Args, Output = Output> + 'a + Send
) -> (<FnOnce<Args, Output = Output> + 'a + Send as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for Fn<Args, Output = Output> + 'a + Sync

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const Fn<Args, Output = Output> + 'a + Sync

fn disassemble(
    ptr: *const Fn<Args, Output = Output> + 'a + Sync
) -> (<Fn<Args, Output = Output> + 'a + Sync as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl DynSized for Any + 'static + Send

type Meta = Vtable

fn assemble(vtable: Vtable, data: *const ()) -> *const Any + 'static + Send

fn disassemble(
    ptr: *const Any + 'static + Send
) -> (<Any + 'static + Send as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for Fn<Args, Output = Output> + 'a + Send

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const Fn<Args, Output = Output> + 'a + Send

fn disassemble(
    ptr: *const Fn<Args, Output = Output> + 'a + Send
) -> (<Fn<Args, Output = Output> + 'a + Send as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for Fn<Args, Output = Output> + 'a

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const Fn<Args, Output = Output> + 'a

fn disassemble(
    ptr: *const Fn<Args, Output = Output> + 'a
) -> (<Fn<Args, Output = Output> + 'a as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<T> DynSized for WrapSized<T>

type Meta = ()

fn assemble((), data: *const ()) -> *const WrapSized<T>

fn disassemble(ptr: *const WrapSized<T>) -> ((), *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

impl<'a, Args, Output> DynSized for FnOnce<Args, Output = Output> + 'a

type Meta = Vtable

fn assemble(
    vtable: Vtable,
    data: *const ()
) -> *const FnOnce<Args, Output = Output> + 'a

fn disassemble(
    ptr: *const FnOnce<Args, Output = Output> + 'a
) -> (<FnOnce<Args, Output = Output> + 'a as DynSized>::Meta, *const ())

fn assemble_mut(meta: Self::Meta, data: *mut ()) -> *mut Self

fn disassemble_mut(ptr: *mut Self) -> (Self::Meta, *mut ())

fn meta(&self) -> Self::Meta

fn data(&self) -> *const ()

fn data_mut(&mut self) -> *mut ()

Implementors

• impl<'a, Args, Output> DynSized for FnMove<Args, Output = Output> + 'a type Meta = Vtable;
• impl<'a, Args, Output> DynSized for FnMove<Args, Output = Output> + 'a + Send type Meta = Vtable;
• impl<D: ?Sized> DynSized for ThinBackend<D, D> where
    D: DynSized,  type Meta = D::Meta;