Struct BorrowRef

pub struct BorrowRef<'a, T: ?Sized + 'a> { /* private fields */ }

Guard for a data borrowed from a slot in the virtual machine.

These guards are necessary, since we need to guarantee certain forms of access depending on what we do. Releasing the guard releases the access.

Implementations

impl<'a, T: ?Sized> BorrowRef<'a, T>

pub fn map<U: ?Sized>(this: Self, m: impl FnOnce(&T) -> &U) -> BorrowRef<'a, U>

Map the reference.

Examples

use rune::runtime::{BorrowRef, Bytes};
use rune::alloc::try_vec;

let bytes = rune::to_value(Bytes::from_vec(try_vec![1, 2, 3, 4]))?;
let bytes = bytes.borrow_ref::<Bytes>()?;

let bytes: BorrowRef<[u8]> = BorrowRef::map(bytes, |bytes| &bytes[0..2]);

assert_eq!(&bytes[..], &[1u8, 2u8][..]);

pub fn try_map<U: ?Sized>( this: Self, m: impl FnOnce(&T) -> Option<&U>, ) -> Result<BorrowRef<'a, U>, Self>

Try to map the reference to a projection.

Examples

use rune::runtime::{BorrowRef, Bytes};
use rune::alloc::try_vec;

let bytes = rune::to_value(Bytes::from_vec(try_vec![1, 2, 3, 4]))?;
let bytes = bytes.borrow_ref::<Bytes>()?;

let Ok(bytes) = BorrowRef::try_map(bytes, |bytes| bytes.get(0..2)) else {
    panic!("Conversion failed");
};

assert_eq!(&bytes[..], &[1u8, 2u8][..]);

Trait Implementations

impl<T: ?Sized> AsRef<T> for BorrowRef<'_, T>

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<T> Debug for BorrowRef<'_, T>

where T: Debug + ?Sized,

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: ?Sized> Deref for BorrowRef<'_, T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.