Trait BorrowForeign

pub trait BorrowForeign<'a>: FreeForeign {
    type Storage: 'a;

    // Required method
    fn borrow_foreign(
        &'a self,
    ) -> BorrowedPointer<'a, Self::Foreign, Self::Storage>;
}

A type for which a C representation can be borrowed without cloning.

Required Associated Types

type Storage: 'a

The type of any extra data that are needed while the BorrowedPointer is alive.

Required Methods

fn borrow_foreign(&'a self) -> BorrowedPointer<'a, Self::Foreign, Self::Storage>

Return a wrapper for a C representation of self. The wrapper borrows the data from self and allows access via a constant pointer.

let s = CString::new("Hello, world!").unwrap();
let borrowed = s.borrow_foreign();
let len = unsafe { libc::strlen(borrowed.as_ptr()) };

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.

Implementations on Foreign Types

impl<'a> BorrowForeign<'a> for bool

type Storage = &'a bool

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for f32

type Storage = &'a f32

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for f64

type Storage = &'a f64

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for i8

type Storage = &'a i8

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for i16

type Storage = &'a i16

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for i32

type Storage = &'a i32

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for i64

type Storage = &'a i64

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for isize

type Storage = &'a isize

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for u8

type Storage = &'a u8

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for u16

type Storage = &'a u16

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for u32

type Storage = &'a u32

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for u64

type Storage = &'a u64

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for usize

type Storage = &'a usize

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a> BorrowForeign<'a> for CStr

type Storage = &'a CStr

fn borrow_foreign(&self) -> BorrowedPointer<'_, c_char, &CStr>

impl<'a, B> BorrowForeign<'a> for Cow<'a, B>

where B: 'a + ToOwned + ?Sized + BorrowForeign<'a>,

type Storage = <B as BorrowForeign<'a>>::Storage

fn borrow_foreign(&'a self) -> BorrowedPointer<'a, B::Foreign, B::Storage>

impl<'a, T> BorrowForeign<'a> for Option<T>

where T: BorrowForeign<'a>,

type Storage = Option<<T as BorrowForeign<'a>>::Storage>

fn borrow_foreign(&'a self) -> BorrowedPointer<'a, Self::Foreign, Self::Storage>

impl<'a, T> BorrowForeign<'a> for [T]

where T: FixedAlloc + FreeForeign<Foreign = T> + BorrowForeign<'a, Storage = &'a T> + 'a,

type Storage = &'a [T]

fn borrow_foreign(&self) -> BorrowedPointer<'_, Self::Foreign, &Self>

impl<'a, T> BorrowForeign<'a> for Box<T>

where T: BorrowForeign<'a>,

type Storage = <T as BorrowForeign<'a>>::Storage

fn borrow_foreign(&'a self) -> BorrowedPointer<'a, Self::Foreign, Self::Storage>

impl<'a, T> BorrowForeign<'a> for Vec<T>

where [T]: BorrowForeign<'a>,

type Storage = <[T] as BorrowForeign<'a>>::Storage

fn borrow_foreign(&'a self) -> BorrowedPointer<'a, Self::Foreign, Self::Storage>

Implementors