Struct abi_stable::std_types::RSliceMut

#[repr(C)]
pub struct RSliceMut<'a, T> { /* fields omitted */ }

Ffi-safe equivalent of &'a mut [T]

As of the writing this documentation the abi stability of &mut [T] is not yet guaranteed.

Lifetime problems

Because RSliceMut dereferences into a mutable slice,you can call slice method on it.

If you call a slice method that returns a borrow into the slice, it will have the lifetime of the let slice:RSliceMut<'a,[T]> variable instead of the 'a lifetime that it's parameterized over.

To get a slice with the same lifetime as an RSliceMut, one must use one of the RSliceMut::{into_slice,into_slice_mut} methods.

Example of what would not work:

use abi_stable::std_types::RSliceMut;

fn into_slice<'a,T>(slic:RSliceMut<'a,T>)->&'a [T] {
    &*slic
}

fn into_slice_mut<'a,T>(slic:RSliceMut<'a,T>)->&'a mut [T] {
    &mut *slic
}

Example of what would work:

use abi_stable::std_types::RSliceMut;

fn into_slice<'a,T>(slic:RSliceMut<'a,T>)->&'a [T] {
    slic.into_slice()
}

fn into_slice_mut<'a,T>(slic:RSliceMut<'a,T>)->&'a mut [T] {
    slic.into_slice_mut()
}

Example

Defining an extern fn that returns a mutable reference to the first element that compares equal to a parameter.

use abi_stable::{
    std_types::RSliceMut,
    sabi_extern_fn,
};

#[sabi_extern_fn]
pub fn find_first_mut<'a,T>(slice_:RSliceMut<'a,T>,element:&T)->Option<&'a mut T>
where
    T:std::cmp::PartialEq
{
    slice_.iter()
        .position(|x| x==element )
        .map(|i| &mut slice_.into_slice_mut()[i] )
}

Methods

impl<'a, T> RSliceMut<'a, T>

pub const fn as_ptr(&self) -> *const T

Gets a raw pointer to the start of the slice.

pub const fn into_mut_ptr(self) -> *mut T

Gets a mutable raw pointer to the start of the slice.

pub const fn len(&self) -> usize

The length (in elements) of this slice.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::<u8>::from_mut_slice(&mut[]).len(), 0);
assert_eq!(RSliceMut::from_mut_slice(&mut[0]).len(), 1);
assert_eq!(RSliceMut::from_mut_slice(&mut[0,1]).len(), 2);
 

pub const fn is_empty(&self) -> bool

Whether this slice is empty.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::<u8>::from_mut_slice(&mut []).is_empty(), true);
assert_eq!(RSliceMut::from_mut_slice(&mut [0]).is_empty(), false);
assert_eq!(RSliceMut::from_mut_slice(&mut [0,1]).is_empty(), false);

pub unsafe fn from_raw_parts_mut(ptr_: *mut T, len: usize) -> Self

Constructs an RSliceMut<'a,T> from a pointer to the first element, and a length.

Safety

Callers must ensure that:

• ptr_ points to valid memory,

• ptr_ .. ptr+len range is àccessible memory.

• ptr_ is aligned to T.

• the data ptr_ points to must be valid for the lifetime of this RSlice<'a,T>

Examples

This function unsafely converts a &mut [T] to an RSliceMut<T>, equivalent to doing RSliceMut::from_mut_slice.

use abi_stable::std_types::RSliceMut;

fn convert<T>(slice_:&mut [T])->RSliceMut<'_,T>{
    let len=slice_.len();
    unsafe{
        RSliceMut::from_raw_parts_mut( slice_.as_mut_ptr(), len )
    }
}

impl<'a, T> RSliceMut<'a, T>

pub fn from_mut(ref_: &'a mut T) -> Self

Converts a mutable reference to T to a single element RSliceMut<'a,T>.

Note:this function does not copy anything.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut(&mut 0), RSliceMut::from_mut_slice(&mut [0]) );
assert_eq!(RSliceMut::from_mut(&mut 1), RSliceMut::from_mut_slice(&mut [1]) );
assert_eq!(RSliceMut::from_mut(&mut 2), RSliceMut::from_mut_slice(&mut [2]) );
 

pub fn from_mut_slice(slic: &'a mut [T]) -> Self

Converts a &'a mut [T] to a RSliceMut<'a,T>.

Example

use abi_stable::std_types::RSliceMut;

let empty:&mut [u8]=&mut [];

assert_eq!(RSliceMut::<u8>::from_mut_slice(&mut[]).as_mut_slice(), empty);
assert_eq!(RSliceMut::from_mut_slice(&mut[0]).as_mut_slice()     , &mut [0][..]);
assert_eq!(RSliceMut::from_mut_slice(&mut[0,1]).as_mut_slice()   , &mut [0,1][..]);
 

Important traits for RSlice<'a, u8>

impl<'a> Read for RSlice<'a, u8>

pub fn slice<I>(&self, i: I) -> RSlice<T> where
    [T]: Index<I, Output = [T]>, 

Creates an RSlice<'a,T> with access to the range range of elements.

This is an inherent method instead of an implementation of the ::std::ops::Index trait because it does not return a reference.

Example

use abi_stable::std_types::{RSliceMut,RSlice};

let slic=&mut[0,1,2,3];
let slic=RSliceMut::from_mut_slice(slic);

assert_eq!(slic.slice(..),RSlice::from_slice(&[0,1,2,3]));
assert_eq!(slic.slice(..2),RSlice::from_slice(&[0,1]));
assert_eq!(slic.slice(2..),RSlice::from_slice(&[2,3]));
assert_eq!(slic.slice(1..3),RSlice::from_slice(&[1,2]));

Important traits for RSliceMut<'a, u8>

impl<'a> Write for RSliceMut<'a, u8>

pub fn slice_mut<'b, I>(&'b mut self, i: I) -> RSliceMut<'b, T> where
    [T]: IndexMut<I, Output = [T]>, 

Creates an RSliceMut<'a,T> with access to the range range of elements.

This is an inherent method instead of an implementation of the ::std::ops::IndexMut trait because it does not return a reference.

Example

use abi_stable::std_types::RSliceMut;

let slic=&mut[0,1,2,3];
let mut slic=RSliceMut::from_mut_slice(slic);

assert_eq!(slic.slice_mut(..),RSliceMut::from_mut_slice(&mut[0,1,2,3]));
assert_eq!(slic.slice_mut(..2),RSliceMut::from_mut_slice(&mut[0,1]));
assert_eq!(slic.slice_mut(2..),RSliceMut::from_mut_slice(&mut[2,3]));
assert_eq!(slic.slice_mut(1..3),RSliceMut::from_mut_slice(&mut[1,2]));

Important traits for RVec<u8>

impl Write for RVec<u8>

pub fn to_rvec(&self) -> RVec<T> where
    T: Clone, 

Creates a new RVec<T> and clones all the elements of this slice into it.

Example

use abi_stable::std_types::{RSliceMut,RVec};

let slic=&mut[0,1,2,3];
let slic=RSliceMut::from_mut_slice(slic);

assert_eq!(slic.slice(..).to_rvec(),RVec::from_slice(&[0,1,2,3]));
assert_eq!(slic.slice(..2).to_rvec(),RVec::from_slice(&[0,1]));
assert_eq!(slic.slice(2..).to_rvec(),RVec::from_slice(&[2,3]));
assert_eq!(slic.slice(1..3).to_rvec(),RVec::from_slice(&[1,2]));

pub fn as_slice(&self) -> &[T]

Creates an &'_ [T] with access to all the elements of this slice.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut_slice(&mut[0,1,2,3]).as_slice(), &[0,1,2,3]);

pub fn into_slice(self) -> &'a [T]

Creates an &'a [T] with access to all the elements of this slice.

This is different to as_slice in that the returned lifetime of this function is larger.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut_slice(&mut[0,1,2,3]).into_slice(), &[0,1,2,3]);

Important traits for RSlice<'a, u8>

impl<'a> Read for RSlice<'a, u8>

pub fn as_rslice(&self) -> RSlice<T>

Creates an RSlice<'_, T> with access to all the elements of this slice.

Example

use abi_stable::std_types::{RSliceMut,RSlice};

assert_eq!(
    RSliceMut::from_mut_slice(&mut[0,1,2,3]).as_rslice(),
    RSlice::from_slice(&[0,1,2,3]),
);

Important traits for RSlice<'a, u8>

impl<'a> Read for RSlice<'a, u8>

pub fn into_rslice(self) -> RSlice<'a, T>

Creates an RSlice<'a, T> with access to all the elements of this slice.

This is different to as_rslice in that the returned lifetime of this function is larger.

Example

use abi_stable::std_types::{RSliceMut,RSlice};

assert_eq!(
    RSliceMut::from_mut_slice(&mut[0,1,2,3]).into_rslice(),
    RSlice::from_slice(&[0,1,2,3]),
);

pub fn as_mut_slice(&mut self) -> &mut [T]

Creates a &'_ mut [T] with access to all the elements of this slice.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut_slice(&mut[0,1,2,3]).as_mut_slice(), &mut [0,1,2,3]);

pub fn into_slice_mut(self) -> &'a mut [T]

Creates a &'a mut [T] with access to all the elements of this slice.

This is different to as_mut_slice in that the returned lifetime of this function is larger.

This will be deprecated in 0.7.0.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut_slice(&mut[0,1,2,3]).into_slice_mut(), &mut [0,1,2,3]);

pub fn into_mut_slice(self) -> &'a mut [T]

Creates a &'a mut [T] with access to all the elements of this slice.

This is different to as_mut_slice in that the returned lifetime of this function is larger.

Example

use abi_stable::std_types::RSliceMut;

assert_eq!(RSliceMut::from_mut_slice(&mut[0,1,2,3]).into_mut_slice(), &mut [0,1,2,3]);

Trait Implementations

impl<'a, T: 'a> AsMut<[T]> for RSliceMut<'a, T>

fn as_mut(&mut self) -> &mut [T]

Performs the conversion.

impl<'a, T: 'a> AsRef<[T]> for RSliceMut<'a, T>

fn as_ref(&self) -> &[T]

Performs the conversion.

impl<'a, T: 'a> Borrow<[T]> for RSliceMut<'a, T>

fn borrow(&self) -> &[T]

Immutably borrows from an owned value.

impl<'a, T: 'a> BorrowMut<[T]> for RSliceMut<'a, T>

fn borrow_mut(&mut self) -> &mut [T]

Mutably borrows from an owned value.

impl<'a, T> Debug for RSliceMut<'a, T> where
    T: Debug, 

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'a, T> Default for RSliceMut<'a, T>

fn default() -> Self

Returns the "default value" for a type.

impl<'a, T> Deref for RSliceMut<'a, T>

type Target = [T]

The resulting type after dereferencing.

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

Dereferences the value.

impl<'a, T> DerefMut for RSliceMut<'a, T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'a, T> Eq for RSliceMut<'a, T> where
    T: Eq, 

impl<'a, T> From<&'a mut [T]> for RSliceMut<'a, T>

Important traits for RSliceMut<'a, u8>

impl<'a> Write for RSliceMut<'a, u8>

fn from(this: &'a mut [T]) -> RSliceMut<'a, T>

Performs the conversion.

impl<'a, T> GetStaticEquivalent_ for RSliceMut<'a, T> where
    T: __StableAbi,
    T: 'a, 

type StaticEquivalent = _static_RSliceMut<'static, __GetStaticEquivalent<T>>

impl<'a, T> Hash for RSliceMut<'a, T> where
    T: Hash, 

fn hash<H>(&self, state: &mut H) where
    H: Hasher, 

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<'a, T> Into<&'a [T]> for RSliceMut<'a, T>

fn into(self) -> &'a [T]

Performs the conversion.

impl<'a, T> Into<&'a mut [T]> for RSliceMut<'a, T>

fn into(self) -> &'a mut [T]

Performs the conversion.

impl<'a, T> IntoIterator for RSliceMut<'a, T>

type Item = &'a mut T

The type of the elements being iterated over.

type IntoIter = IterMut<'a, T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> IterMut<'a, T>

Creates an iterator from a value.

impl<'a, T> IntoReprRust for RSliceMut<'a, T>

type ReprRust = &'a mut [T]

fn into_rust(self) -> Self::ReprRust

impl<'a, T> Ord for RSliceMut<'a, T> where
    T: Ord, 

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<'a, T> PartialEq<RSliceMut<'a, T>> for RSliceMut<'a, T> where
    T: PartialEq, 

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, T> PartialOrd<RSliceMut<'a, T>> for RSliceMut<'a, T> where
    T: PartialOrd, 

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use] fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use] fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use] fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use] fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<'a, T> Send for RSliceMut<'a, T> where
    &'a mut [T]: Send, 

impl<'a, T> Serialize for RSliceMut<'a, T> where
    T: Serialize, 

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
    S: Serializer, 

Serialize this value into the given Serde serializer.

impl<'a, T> SharedStableAbi for RSliceMut<'a, T> where
    T: __StableAbi,
    T: 'a, 

type IsNonZeroType = False

Whether this type has a single invalid bit-pattern.

type Kind = __ValueKind

The kind of abi stability of this type,there are 2:

const S_LAYOUT: &'static TypeLayout

The layout of the type provided by implementors.

const S_ABI_CONSTS: AbiConsts

impl<'a, T> Sync for RSliceMut<'a, T> where
    &'a mut [T]: Sync, 

impl<'a> Write for RSliceMut<'a, u8>

fn write(&mut self, data: &[u8]) -> Result<usize>

Write a buffer into this writer, returning how many bytes were written.

fn write_all(&mut self, data: &[u8]) -> Result<()>

Attempts to write an entire buffer into this writer.

fn flush(&mut self) -> Result<()>

Flush this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn write_fmt(&mut self, fmt: Arguments) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Write.