Struct abi_stable::erased_types::DynTrait

#[repr(C)]
pub struct DynTrait<'borr, P, I, EV = ()>
where
    P: GetPointerKind,
{ /* private fields */ }

DynTrait implements ffi-safe trait objects, for a selection of traits.

Passing opaque values around with DynTrait<_>

One can pass non-StableAbi types around by using type erasure, using this type.

It generally looks like DynTrait<'borrow, Pointer<()>, Interface>, where:

• 'borrow is the borrow that the type that was erased had.

• Pointer is a pointer type that implements AsPtr.

• Interface is an InterfaceType, which describes what traits are required when constructing the DynTrait<_> and which ones it implements.

Construction

To construct a DynTrait<_> one can use these associated functions:

• from_value: Can be constructed from the value directly.Requires a 'static value.

• from_ptr Can be constructed from a pointer of a value.Requires a 'static value.

• from_borrowing_value: Can be constructed from the value directly.Cannot downcast the DynTrait afterwards.

• from_borrowing_ptr Can be constructed from a pointer of a value.Cannot downcast the DynTrait afterwards.

DynTrait uses the impls of the value in methods, which means that the pointer itself does not have to implement those traits,

Trait object

DynTrait<'borrow, Pointer<()>, Interface> can be used as a trait object for any combination of the traits listed below.

These are the traits:

• Send

• Sync

• Unpin

• Iterator

• DoubleEndedIterator

• std::fmt::Write

• std::io::Write

• std::io::Seek

• std::io::Read

• std::io::BufRead

• Clone

• Display

• Debug

• std::error::Error

• Default: Can only be called as an inherent method.

• Eq

• PartialEq

• Ord

• PartialOrd

• Hash

• serde::Deserialize: first deserializes from a string, and then calls the objects’ Deserialize impl.

• serde::Serialize: first calls the objects’ Deserialize impl, then serializes that as a string.

Deconstruction

DynTrait<_> can then be unwrapped into a concrete type, within the same dynamic library/executable that constructed it, using these (fallible) conversion methods:

• downcast_into: Unwraps into a pointer to T.Requires T:'static.

• downcast_as: Unwraps into a &T.Requires T:'static.

• downcast_as_mut: Unwraps into a &mut T.Requires T:'static.

DynTrait cannot be converted back if it was created using DynTrait::from_borrowing_*.

Passing DynTrait between dynamic libraries

Passing DynTrait between dynamic libraries (as in between the dynamic libraries directly loaded by the same binary/dynamic library) may cause the program to panic at runtime with an error message stating that the trait is not implemented for the specific interface.

This can only happen if you are passing DynTrait between dynamic libraries, or if DynTrait was instantiated in the parent passed to a child, a DynTrait instantiated in a child dynamic library passed to the parent should not cause a panic, it would be a bug.

        binary
  _________|___________
lib0      lib1      lib2
  |         |         |
lib00    lib10      lib20

In this diagram passing a DynTrait constructed in lib00 to anything other than the binary or lib0 will cause the panic to happen if:

• The InterfaceType requires extra traits in the version of the Interface that lib1 and lib2 know about (that the binary does not require).

• lib1 or lib2 attempt to call methods that require the traits that were added to the InterfaceType, in versions of that interface that only they know about.

Examples

In the Readme

The primary example using DynTrait<_> is in the readme.

Readme is in the repository for this crate, crates.io, lib.rs.

Serialization/Deserialization

The DeserializeDyn and SerializeType demonstrate how DynTrait can be de/serialized.

Comparing DynTraits

This is only possible if the erased types don’t contain borrows, and they are not constructed using DynTrait::from_borrowing_* methods.

DynTraits wrapping different pointer types can be compared with each other, it simply uses the values’ implementation of PartialEq.

use abi_stable::{
    erased_types::interfaces::PartialEqInterface,
    std_types::{RArc, RBox},
    DynTrait, RMut, RRef,
};

{
    // `DynTrait`s constructed from `&` are `DynTrait<'_, RRef<'_, ()>, _>`
    // since `&T` can't soundly be transmuted back and forth into `&()`
    let left: DynTrait<'static, RRef<'_, ()>, PartialEqInterface> =
        DynTrait::from_ptr(&100);

    let mut n100 = 100;
    // `DynTrait`s constructed from `&mut` are `DynTrait<'_, RMut<'_, ()>, _>`
    // since `&mut T` can't soundly be transmuted back and forth into `&mut ()`
    let right: DynTrait<'static, RMut<'_, ()>, PartialEqInterface> =
        DynTrait::from_ptr(&mut n100).interface(PartialEqInterface);

    assert_eq!(left, right);
}
{
    let left: DynTrait<'static, RBox<()>, PartialEqInterface> =
        DynTrait::from_value(200);

    let right: DynTrait<'static, RArc<()>, _> =
        DynTrait::from_ptr(RArc::new(200)).interface(PartialEqInterface);

    assert_eq!(left, right);
}

Writing to a DynTrait

This is an example of using the write!() macro with DynTrait.

use abi_stable::{erased_types::interfaces::FmtWriteInterface, DynTrait, RMut};

use std::fmt::Write;

let mut buffer = String::new();

let mut wrapped: DynTrait<'static, RMut<'_, ()>, FmtWriteInterface> =
    DynTrait::from_ptr(&mut buffer);

write!(wrapped, "Foo").unwrap();
write!(wrapped, "Bar").unwrap();
write!(wrapped, "Baz").unwrap();

drop(wrapped);

assert_eq!(&buffer[..], "FooBarBaz");

Iteration

Using DynTrait as an Iterator and DoubleEndedIterator.

use abi_stable::{erased_types::interfaces::DEIteratorInterface, DynTrait};

let mut wrapped = DynTrait::from_value(0..=10).interface(DEIteratorInterface::NEW);

assert_eq!(
    wrapped.by_ref().take(5).collect::<Vec<_>>(),
    vec![0, 1, 2, 3, 4]
);

assert_eq!(wrapped.rev().collect::<Vec<_>>(), vec![10, 9, 8, 7, 6, 5]);

Making pointers compatible with DynTrait

To make pointers compatible with DynTrait, they must imlement the abi_stable::pointer_trait::{ GetPointerKind, AsPtr, AsMutPtr, CanTransmuteElement} traits as shown in the example.

GetPointerKind should generally be implemented with type Kind = PK_SmartPointer. The exception is in the case that it is a #[repr(transparent)] wrapper around a RRef/RMut/*const T/*mut T/NonNull, in which case it should implement GetPointerKind<Kind = PK_Reference> (when it has shared reference semantics) or GetPointerKind<Kind = PK_MutReference> (when it has mutable reference semantics).

Example

This is an example of a newtype wrapping an RBox, demonstrating that the pointer type doesn’t have to implement the traits in the InterfaceType, it’s the value it points to.

     
use abi_stable::DynTrait;

fn main() {
    let lines = "line0\nline1\nline2";
    let mut iter = NewtypeBox::new(lines.lines());

    // The type annotation here is just to show the type, it's not necessary.
    let mut wrapper: DynTrait<'_, NewtypeBox<()>, IteratorInterface> =
        DynTrait::from_borrowing_ptr(iter);

    // You can clone the DynTrait!
    let clone = wrapper.clone();

    assert_eq!(wrapper.next(), Some("line0"));
    assert_eq!(wrapper.next(), Some("line1"));
    assert_eq!(wrapper.next(), Some("line2"));
    assert_eq!(wrapper.next(), None);

    assert_eq!(
        clone.rev().collect::<Vec<_>>(),
        vec!["line2", "line1", "line0"],
    )
}

#[repr(C)]
#[derive(StableAbi)]
#[sabi(impl_InterfaceType(
    Sync,
    Send,
    Iterator,
    DoubleEndedIterator,
    Clone,
    Debug
))]
pub struct IteratorInterface;

impl<'a> IteratorItem<'a> for IteratorInterface {
    type Item = &'a str;
}

/////////////////////////////////////////

use std::ops::{Deref, DerefMut};

use abi_stable::{
    erased_types::IteratorItem,
    pointer_trait::{
        AsMutPtr, AsPtr, CanTransmuteElement, GetPointerKind, PK_SmartPointer,
    },
    std_types::RBox,
    type_level::bools::True,
    InterfaceType, StableAbi,
};

#[repr(transparent)]
#[derive(Default, Clone, StableAbi)]
pub struct NewtypeBox<T> {
    box_: RBox<T>,
}

impl<T> NewtypeBox<T> {
    pub fn new(value: T) -> Self {
        Self {
            box_: RBox::new(value),
        }
    }
}

unsafe impl<T> GetPointerKind for NewtypeBox<T> {
    // This is a smart pointer because `RBox` is one.
    type Kind = PK_SmartPointer;
    type PtrTarget = T;
}

// safety: Does not create an intermediate `&T` to get a pointer to `T`.
unsafe impl<T> AsPtr for NewtypeBox<T> {
    fn as_ptr(&self) -> *const T {
        self.box_.as_ptr()
    }
}

// safety: Does not create an intermediate `&mut T` to get a pointer to `T`
unsafe impl<T> AsMutPtr for NewtypeBox<T> {
    fn as_mut_ptr(&mut self) -> *mut T {
        self.box_.as_mut_ptr()
    }
}

// safety:
// NewtypeBox is safe to transmute, because RBox (the pointer type it wraps)
// is safe to transmute
unsafe impl<T, O> CanTransmuteElement<O> for NewtypeBox<T> {
    type TransmutedPtr = NewtypeBox<O>;

    unsafe fn transmute_element_(self) -> Self::TransmutedPtr {
        let box_: RBox<O> = self.box_.transmute_element_();
        NewtypeBox { box_ }
    }
}

Implementations

impl<I> DynTrait<'static, RBox<()>, I>

pub fn from_value<T>(object: T) -> Self

where T: 'static, VTable_Ref<'static, RBox<()>, I>: MakeVTable<'static, T, RBox<T>, TD_CanDowncast>,

Constructs the DynTrait<_> from a type that doesn’t borrow anything.

Example

use abi_stable::{
    erased_types::interfaces::DebugDisplayInterface, std_types::RBox, DynTrait,
};

// DebugDisplayInterface is `Debug + Display + Sync + Send`
let to: DynTrait<'static, RBox<()>, DebugDisplayInterface> =
    DynTrait::from_value(3u8);

assert_eq!(format!("{}", to), "3");
assert_eq!(format!("{:?}", to), "3");

impl<P, I> DynTrait<'static, P, I>

where P: GetPointerKind,

pub fn from_ptr<OrigPtr>(object: OrigPtr) -> Self

where OrigPtr: GetPointerKind + CanTransmuteElement<(), TransmutedPtr = P>, OrigPtr::PtrTarget: 'static, VTable_Ref<'static, P, I>: MakeVTable<'static, OrigPtr::PtrTarget, OrigPtr, TD_CanDowncast>,

Constructs the DynTrait<_> from a pointer to a type that doesn’t borrow anything.

Example

use abi_stable::{
    erased_types::interfaces::DebugDisplayInterface,
    std_types::{RArc, RBox},
    DynTrait, RMut, RRef,
};

// Constructing a DynTrait from a `&T`
{
    // `DynTrait`s constructed from `&` are `DynTrait<'_, RRef<'_, ()>, _>`
    // since `&T` can't soundly be transmuted back and forth into `&()`
    let rref: DynTrait<'static, RRef<'_, ()>, DebugDisplayInterface> =
        DynTrait::from_ptr(&21i32);

    assert_eq!(format!("{:?}", rref), "21");
    assert_eq!(format!("{}", rref), "21");
}
// Constructing a DynTrait from a `&mut T`
{
    let mmut = &mut "hello";
    // `DynTrait`s constructed from `&mut` are `DynTrait<'_, RMut<'_, ()>, _>`
    // since `&mut T` can't soundly be transmuted back and forth into `&mut ()`
    let rmut: DynTrait<'static, RMut<'_, ()>, DebugDisplayInterface> =
        DynTrait::from_ptr(mmut).interface(DebugDisplayInterface);

    assert_eq!(format!("{:?}", rmut), r#""hello""#);
    assert_eq!(format!("{}", rmut), "hello");
}
// Constructing a DynTrait from a `RBox<T>`
{
    let boxed: DynTrait<'static, RBox<()>, DebugDisplayInterface> =
        DynTrait::from_ptr(RBox::new(false));

    assert_eq!(format!("{:?}", boxed), "false");
    assert_eq!(format!("{}", boxed), "false");
}
// Constructing a DynTrait from an `RArc<T>`
{
    let arc: DynTrait<'static, RArc<()>, DebugDisplayInterface> =
        DynTrait::from_ptr(RArc::new(30u32)).interface(DebugDisplayInterface);

    assert_eq!(format!("{:?}", arc), "30");
}

impl<'borr, I> DynTrait<'borr, RBox<()>, I>

pub fn from_borrowing_value<T>(object: T) -> Self

where T: 'borr, VTable_Ref<'borr, RBox<()>, I>: MakeVTable<'borr, T, RBox<T>, TD_Opaque>,

Constructs the DynTrait<_> from a value with a 'borr borrow.

Cannot downcast the DynTrait afterwards.

Example

use abi_stable::{
    erased_types::interfaces::DebugDisplayInterface, std_types::RBox, DynTrait,
};

// DebugDisplayInterface is `Debug + Display + Sync + Send`
let to: DynTrait<'static, RBox<()>, DebugDisplayInterface> =
    DynTrait::from_borrowing_value(3u8);

assert_eq!(format!("{}", to), "3");
assert_eq!(format!("{:?}", to), "3");

// `DynTrait`s constructed using the `from_borrowing_*` constructors
// can't be downcasted.
assert_eq!(to.downcast_as::<u8>().ok(), None);

impl<'borr, P, I> DynTrait<'borr, P, I>

where P: GetPointerKind,

pub fn from_borrowing_ptr<OrigPtr>(object: OrigPtr) -> Self

where OrigPtr: GetPointerKind + 'borr + CanTransmuteElement<(), TransmutedPtr = P>, OrigPtr::PtrTarget: 'borr, VTable_Ref<'borr, P, I>: MakeVTable<'borr, OrigPtr::PtrTarget, OrigPtr, TD_Opaque>,

Constructs the DynTrait<_> from a pointer to the erased type with a 'borr borrow.

Cannot downcast the DynTrait afterwards.

Example

use abi_stable::{
    erased_types::interfaces::DebugDisplayInterface,
    std_types::{RArc, RBox},
    DynTrait, RMut, RRef,
};

// Constructing a DynTrait from a `&T`
{
    // `DynTrait`s constructed from `&` are `DynTrait<'_, RRef<'_, ()>, _>`
    // since `&T` can't soundly be transmuted back and forth into `&()`
    let rref: DynTrait<'_, RRef<'_, ()>, DebugDisplayInterface> =
        DynTrait::from_borrowing_ptr(&34i32);

    assert_eq!(format!("{:?}", rref), "34");
    assert_eq!(format!("{}", rref), "34");
}
// Constructing a DynTrait from a `&mut T`
{
    let mmut = &mut "world";
    // `DynTrait`s constructed from `&mut` are `DynTrait<'_, RMut<'_, ()>, _>`
    // since `&mut T` can't soundly be transmuted back and forth into `&mut ()`
    let rmut: DynTrait<'_, RMut<'_, ()>, DebugDisplayInterface> =
        DynTrait::from_borrowing_ptr(mmut).interface(DebugDisplayInterface);

    assert_eq!(format!("{:?}", rmut), r#""world""#);
    assert_eq!(format!("{}", rmut), "world");
}
// Constructing a DynTrait from a `RBox<T>`
{
    let boxed: DynTrait<'_, RBox<()>, DebugDisplayInterface> =
        DynTrait::from_borrowing_ptr(RBox::new(true));

    assert_eq!(format!("{:?}", boxed), "true");
    assert_eq!(format!("{}", boxed), "true");
}
// Constructing a DynTrait from an `RArc<T>`
{
    let arc: DynTrait<'_, RArc<()>, _> =
        DynTrait::from_borrowing_ptr(RArc::new('a')).interface(DebugDisplayInterface);

    assert_eq!(format!("{:?}", arc), "'a'");
    assert_eq!(format!("{}", arc), "a");
}

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where P: AsPtr<PtrTarget = ()>,

pub fn with_extra_value<OrigPtr, Downcasting>( ptr: OrigPtr, extra_value: EV, ) -> DynTrait<'borr, P, I, EV>

where OrigPtr: GetPointerKind + CanTransmuteElement<(), TransmutedPtr = P>, OrigPtr::PtrTarget: 'borr, VTable_Ref<'borr, P, I>: MakeVTable<'borr, OrigPtr::PtrTarget, OrigPtr, Downcasting>,

Constructs an DynTrait from an erasable pointer and an extra value.

Example

use abi_stable::{
    erased_types::{interfaces::DebugDisplayInterface, TD_Opaque},
    DynTrait, RRef,
};

// DebugDisplayInterface is `Debug + Display + Sync + Send`
let to: DynTrait<'static, RRef<()>, DebugDisplayInterface, usize> =
    DynTrait::with_extra_value::<_, TD_Opaque>(&55u8, 100usize);

assert_eq!(format!("{}", to), "55");
assert_eq!(format!("{:?}", to), "55");

assert_eq!(to.sabi_extra_value(), &100);

impl<'borr, 'a, I, EV> DynTrait<'borr, RRef<'a, ()>, I, EV>

pub const fn from_const<T, Downcasting>( ptr: &'a T, can_it_downcast: Downcasting, extra_value: EV, ) -> Self

where VTable_Ref<'borr, RRef<'a, ()>, I>: MakeVTable<'borr, T, &'a T, Downcasting>, T: 'borr,

This function allows constructing a DynTrait in a constant/static.

Parameters

ptr: a reference to the value.

can_it_downcast can be either:

• TD_CanDowncast: Which allows the trait object to be downcasted, requires that the value implements any.

• TD_Opaque: Which does not allow the trait object to be downcasted.

extra_value: This is used by #[sabi_trait] trait objects to store their vtable inside DynTrait.

Example

use abi_stable::{
    erased_types::{
        interfaces::DebugDisplayInterface, DynTrait, TD_Opaque,
    },
    sabi_types::RRef,
};

static STRING: &str = "What the heck";

static DYN: DynTrait<'static, RRef<'static, ()>, DebugDisplayInterface, ()> =
    DynTrait::from_const(&STRING, TD_Opaque, ());

fn main() {
    assert_eq!(format!("{}", DYN), format!("{}", STRING));
    assert_eq!(format!("{:?}", DYN), format!("{:?}", STRING));
}

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where P: GetPointerKind,

pub const fn interface(self, _interface: I) -> Self

where I: InterfaceType,

For inferring the I type parameter.

impl<P, I, EV> DynTrait<'static, P, I, EV>

where P: GetPointerKind,

pub fn sabi_is_same_type<Other, I2, EV2>( &self, other: &DynTrait<'static, Other, I2, EV2>, ) -> bool

where I2: InterfaceType, Other: GetPointerKind,

Allows checking whether 2 DynTrait<_>s have a value of the same type.

Notes:

• Types from different dynamic libraries/executables are never considered equal.

• DynTraits constructed using DynTrait::from_borrowing_* are never considered to wrap the same type.

impl<'borr, P, I, EV> DynTrait<'borr, P, I, PrefixRef<EV>>

where P: GetPointerKind,

pub const fn sabi_et_vtable(&self) -> PrefixRef<EV>

A vtable used by #[sabi_trait] derived trait objects.

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where P: GetPointerKind,

pub const fn sabi_extra_value(&self) -> &EV

Gets access to the extra value that was stored in this DynTrait in the with_extra_value constructor.

Example

use abi_stable::{erased_types::TD_Opaque, DynTrait, RRef};

let to: DynTrait<'static, RRef<()>, (), char> =
    DynTrait::with_extra_value::<_, TD_Opaque>(&55u8, 'Z');

assert_eq!(to.sabi_extra_value(), &'Z');

pub fn sabi_object_address(&self) -> usize

where P: AsPtr,

Returns the address of the wrapped object.

Example

use abi_stable::{erased_types::TD_Opaque, DynTrait, RRef};

let reff = &55u8;

let to: DynTrait<'static, RRef<()>, ()> = DynTrait::from_ptr(reff);

assert_eq!(to.sabi_object_address(), reff as *const _ as usize);

pub fn sabi_erased_ref(&self) -> RRef<'_, ErasedObject>

where P: AsPtr,

Gets a reference pointing to the erased object.

Example

use abi_stable::{std_types::RBox, DynTrait};

let to: DynTrait<'static, RBox<()>, ()> = DynTrait::from_value(66u8);

unsafe {
    assert_eq!(to.sabi_erased_ref().transmute_into_ref::<u8>(), &66);
}

pub fn sabi_erased_mut(&mut self) -> RMut<'_, ErasedObject>

where P: AsMutPtr,

Gets a mutable reference pointing to the erased object.

Example

use abi_stable::{std_types::RBox, DynTrait};

let mut to: DynTrait<'static, RBox<()>, ()> = DynTrait::from_value("hello");

unsafe {
    assert_eq!(
        to.sabi_erased_mut().transmute_into_mut::<&str>(),
        &mut "hello"
    );
}

pub fn sabi_as_rref(&self) -> RRef<'_, ()>

where P: AsPtr,

Gets an RRef pointing to the erased object.

Example

use abi_stable::{std_types::RBox, DynTrait};

let to: DynTrait<'static, RBox<()>, ()> = DynTrait::from_value(66u8);

unsafe {
    assert_eq!(to.sabi_as_rref().transmute_into_ref::<u8>(), &66);
}

pub fn sabi_as_rmut(&mut self) -> RMut<'_, ()>

where P: AsMutPtr,

Gets an RMut pointing to the erased object.

Example

use abi_stable::{std_types::RBox, DynTrait};

let mut to: DynTrait<'static, RBox<()>, ()> = DynTrait::from_value("hello");

unsafe {
    assert_eq!(to.sabi_as_rmut().transmute_into_mut::<&str>(), &mut "hello");
}

pub fn sabi_with_value<F, R>(self, f: F) -> R

where P: OwnedPointer<PtrTarget = ()>, F: FnOnce(MovePtr<'_, ()>) -> R,

Calls the f callback with an MovePtr pointing to the erased object.

Example

use abi_stable::{
    sabi_types::MovePtr,
    std_types::{RBox, RString, RVec},
    DynTrait,
};

let to: DynTrait<'static, RBox<()>, ()> =
    DynTrait::from_value(RString::from("foobarbaz"));

let string = to.sabi_with_value(|x| {
    // SAFETY: the erased object is an RString constructed in the current binary.
    unsafe {
        MovePtr::into_inner(MovePtr::transmute::<RString>(x))
    }
});

assert_eq!(string, "foobarbaz");

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where P: GetPointerKind,

pub fn downcast_into<T>(self) -> Result<P::TransmutedPtr, UneraseError<Self>>

where T: 'static, P: CanTransmuteElement<T>,

Unwraps the DynTrait<_> into a pointer of the concrete type that it was constructed with.

T is required to not borrow anything.

Errors

This will return an error in any of these conditions:

• It is called in a dynamic library/binary outside the one from which this DynTrait<_> was constructed.

• The DynTrait was constructed using a from_borrowing_* method

• T is not the concrete type this DynTrait<_> was constructed with.

Example

use abi_stable::{
    std_types::{RArc, RBox},
    DynTrait,
};

{
    fn to() -> DynTrait<'static, RBox<()>, ()> {
        DynTrait::from_value(b'A')
    }

    assert_eq!(to().downcast_into::<u8>().ok(), Some(RBox::new(b'A')));
    assert_eq!(to().downcast_into::<u16>().ok(), None);
}
{
    fn to() -> DynTrait<'static, RArc<()>, ()> {
        DynTrait::from_ptr(RArc::new(b'B'))
    }

    assert_eq!(to().downcast_into::<u8>().ok(), Some(RArc::new(b'B')));
    assert_eq!(to().downcast_into::<u16>().ok(), None);
}

pub fn downcast_as<T>(&self) -> Result<&T, UneraseError<&Self>>

where T: 'static, P: AsPtr,

Unwraps the DynTrait<_> into a reference of the concrete type that it was constructed with.

T is required to not borrow anything.

Errors

This will return an error in any of these conditions:

• It is called in a dynamic library/binary outside the one from which this DynTrait<_> was constructed.

• The DynTrait was constructed using a from_borrowing_* method

• T is not the concrete type this DynTrait<_> was constructed with.

Example

use abi_stable::{std_types::RArc, DynTrait, RMut, RRef};

{
    let to: DynTrait<'static, RRef<'_, ()>, ()> = DynTrait::from_ptr(&9u8);

    assert_eq!(to.downcast_as::<u8>().ok(), Some(&9u8));
    assert_eq!(to.downcast_as::<u16>().ok(), None);
}
{
    let mut val = 7u8;

    let to: DynTrait<'static, RMut<'_, ()>, ()> =
        DynTrait::from_ptr(&mut val);

    assert_eq!(to.downcast_as::<u8>().ok(), Some(&7));
    assert_eq!(to.downcast_as::<u16>().ok(), None);
}
{
    let to: DynTrait<'static, RArc<()>, ()> =
        DynTrait::from_ptr(RArc::new(1u8));

    assert_eq!(to.downcast_as::<u8>().ok(), Some(&1u8));
    assert_eq!(to.downcast_as::<u16>().ok(), None);
}

pub fn downcast_as_mut<T>(&mut self) -> Result<&mut T, UneraseError<&mut Self>>

where T: 'static, P: AsMutPtr,

Unwraps the DynTrait<_> into a mutable reference of the concrete type that it was constructed with.

T is required to not borrow anything.

Errors

This will return an error in any of these conditions:

• It is called in a dynamic library/binary outside the one from which this DynTrait<_> was constructed.

• The DynTrait was constructed using a from_borrowing_* method

• T is not the concrete type this DynTrait<_> was constructed with.

Example

use abi_stable::{std_types::RBox, DynTrait, RMut};

{
    let mut val = 7u8;

    let mut to: DynTrait<'static, RMut<'_, ()>, ()> =
        DynTrait::from_ptr(&mut val);

    assert_eq!(to.downcast_as_mut::<u8>().ok(), Some(&mut 7));
    assert_eq!(to.downcast_as_mut::<u16>().ok(), None);
}
{
    let mut to: DynTrait<'static, RBox<()>, ()> =
        DynTrait::from_ptr(RBox::new(1u8));

    assert_eq!(to.downcast_as_mut::<u8>().ok(), Some(&mut 1u8));
    assert_eq!(to.downcast_as_mut::<u16>().ok(), None);
}

pub unsafe fn unchecked_downcast_into<T>(self) -> P::TransmutedPtr

where P: AsPtr + CanTransmuteElement<T>,

Unwraps the DynTrait<_> into a pointer to T, without checking whether T is the type that the DynTrait was constructed with.

Safety

You must check that T is the type that DynTrait was constructed with through other means.

Example

use abi_stable::{
    std_types::{RArc, RBox},
    DynTrait,
};

unsafe {
    fn to() -> DynTrait<'static, RBox<()>, ()> {
        DynTrait::from_value(b'A')
    }

    assert_eq!(to().unchecked_downcast_into::<u8>(), RBox::new(b'A'));
}
unsafe {
    fn to() -> DynTrait<'static, RArc<()>, ()> {
        DynTrait::from_ptr(RArc::new(b'B'))
    }

    assert_eq!(to().unchecked_downcast_into::<u8>(), RArc::new(b'B'));
}

pub unsafe fn unchecked_downcast_as<T>(&self) -> &T

where P: AsPtr,

Unwraps the DynTrait<_> into a reference to T, without checking whether T is the type that the DynTrait was constructed with.

Safety

You must check that T is the type that DynTrait was constructed with through other means.

Example

use abi_stable::{std_types::RArc, DynTrait, RMut, RRef};

unsafe {
    let to: DynTrait<'static, RRef<'_, ()>, ()> = DynTrait::from_ptr(&9u8);

    assert_eq!(to.unchecked_downcast_as::<u8>(), &9u8);
}
unsafe {
    let mut val = 7u8;

    let to: DynTrait<'static, RMut<'_, ()>, ()> =
        DynTrait::from_ptr(&mut val);

    assert_eq!(to.unchecked_downcast_as::<u8>(), &7);
}
unsafe {
    let to: DynTrait<'static, RArc<()>, ()> =
        DynTrait::from_ptr(RArc::new(1u8));

    assert_eq!(to.unchecked_downcast_as::<u8>(), &1u8);
}

pub unsafe fn unchecked_downcast_as_mut<T>(&mut self) -> &mut T

where P: AsMutPtr,

Unwraps the DynTrait<_> into a mutable reference to T, without checking whether T is the type that the DynTrait was constructed with.

Safety

You must check that T is the type that DynTrait was constructed with through other means.

Example

use abi_stable::{std_types::RBox, DynTrait, RMut};

unsafe {
    let mut val = 7u8;

    let mut to: DynTrait<'static, RMut<'_, ()>, ()> =
        DynTrait::from_ptr(&mut val);

    assert_eq!(to.unchecked_downcast_as_mut::<u8>(), &mut 7);
}
unsafe {
    let mut to: DynTrait<'static, RBox<()>, ()> =
        DynTrait::from_ptr(RBox::new(1u8));

    assert_eq!(to.unchecked_downcast_as_mut::<u8>(), &mut 1u8);
}

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where P: GetPointerKind, I: InterfaceType,

pub fn reborrow<'re>(&'re self) -> DynTrait<'borr, RRef<'re, ()>, I, EV>

where P: AsPtr<PtrTarget = ()>, PrivStruct: ReborrowBounds<I::Send, I::Sync>, EV: Copy,

Creates a shared reborrow of this DynTrait.

The reborrowed DynTrait cannot use these methods:

• DynTrait::default

This is only callable if DynTrait is either Send + Sync or !Send + !Sync.

Example

use abi_stable::{
    erased_types::interfaces::DebugDisplayInterface,
    std_types::RBox,
    type_level::{impl_enum::Implemented, trait_marker},
    DynTrait, InterfaceType, RRef,
};

let to: DynTrait<'static, RBox<()>, DebugDisplayInterface> =
    DynTrait::from_value(1337_u16);

assert_eq!(debug_string(to.reborrow()), "1337");

fn debug_string<I>(to: DynTrait<'_, RRef<'_, ()>, I>) -> String
where
    I: InterfaceType<Debug = Implemented<trait_marker::Debug>>,
{
    format!("{:?}", to)
}

pub fn reborrow_mut<'re>(&'re mut self) -> DynTrait<'borr, RMut<'re, ()>, I, EV>

where P: AsMutPtr<PtrTarget = ()>, PrivStruct: ReborrowBounds<I::Send, I::Sync>, EV: Copy,

Creates a mutable reborrow of this DynTrait.

The reborrowed DynTrait cannot use these methods:

• DynTrait::default

• DynTrait::clone

This is only callable if DynTrait is either Send + Sync or !Send + !Sync.

Example

use abi_stable::{
    erased_types::interfaces::DEIteratorInterface, std_types::RBox, DynTrait,
};

let mut to = DynTrait::from_value(0_u8..=255).interface(DEIteratorInterface::NEW);

assert_eq!(both_ends(to.reborrow_mut()), (Some(0), Some(255)));
assert_eq!(both_ends(to.reborrow_mut()), (Some(1), Some(254)));
assert_eq!(both_ends(to.reborrow_mut()), (Some(2), Some(253)));
assert_eq!(both_ends(to.reborrow_mut()), (Some(3), Some(252)));

fn both_ends<I>(mut to: I) -> (Option<I::Item>, Option<I::Item>)
where
    I: DoubleEndedIterator,
{
    (to.next(), to.next_back())
}

impl<'borr, P, I, EV> DynTrait<'borr, P, I, EV>

where I: InterfaceType + 'borr, EV: 'borr, P: AsPtr,

pub fn default(&self) -> Self

where P: AsPtr + GetPointerKind<Kind = PK_SmartPointer>, I: InterfaceType<Default = Implemented<Default>>, EV: Copy,

Constructs a DynTrait<P, I> with the default value for P.

Reborrowing

This cannot be called with a reborrowed DynTrait:

let object = DynTrait::from_value(()).interface(DefaultInterface);
let borrow = object.reborrow();
let _ = borrow.default();

let object = DynTrait::from_value(()).interface(DefaultInterface);
let borrow = object.reborrow_mut();
let _ = borrow.default();

Example

use abi_stable::{erased_types::interfaces::DebugDefEqInterface, DynTrait};

{
    let object = DynTrait::from_value(true).interface(DebugDefEqInterface);

    assert_eq!(
        object.default(),
        DynTrait::from_value(false).interface(DebugDefEqInterface)
    );
}
{
    let object = DynTrait::from_value(123u8).interface(DebugDefEqInterface);

    assert_eq!(
        object.default(),
        DynTrait::from_value(0u8).interface(DebugDefEqInterface)
    );
}

pub fn serialize_into_proxy<'a>(&'a self) -> Result<I::ProxyType, RBoxError>

where P: AsPtr, I: InterfaceType<Serialize = Implemented<Serialize>> + GetSerializeProxyType<'a>,

It serializes a DynTrait<_> into a string by using <ConcreteType as SerializeType>::serialize_impl.

pub fn deserialize_from_proxy<'de>(proxy: I::Proxy) -> Result<Self, RBoxError>

where P: 'borr + AsPtr, I: DeserializeDyn<'de, Self>,

Deserializes a DynTrait<'borr, _> from a proxy type, by using <I as DeserializeDyn<'borr, Self>>::deserialize_dyn.

impl<'lt, I, EV: Clone> DynTrait<'lt, RArc<()>, I, EV>

pub fn shallow_clone(&self) -> Self

Does a shallow clone of the object, just incrementing the reference counter

impl<'borr, P, I, Item, EV> DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: IteratorItemOrDefault<'borr, Item = Item> + InterfaceType<Iterator = Implemented<Iterator>>, Item: 'borr,

pub fn skip_eager(&mut self, n: usize)

Eagerly skips n elements from the iterator.

This method is faster than using Iterator::skip.

Example

let mut iter = 0..20;
let mut wrapped = DynTrait::from_ptr(&mut iter).interface(IteratorInterface::NEW);

assert_eq!(wrapped.next(), Some(0));

wrapped.skip_eager(2);

assert_eq!(wrapped.next(), Some(3));
assert_eq!(wrapped.next(), Some(4));
assert_eq!(wrapped.next(), Some(5));

wrapped.skip_eager(2);

assert_eq!(wrapped.next(), Some(8));
assert_eq!(wrapped.next(), Some(9));

wrapped.skip_eager(9);

assert_eq!(wrapped.next(), Some(19));
assert_eq!(wrapped.next(), None);

pub fn extending_rvec( &mut self, buffer: &mut RVec<Item>, taking: ROption<usize>, )

Extends the RVec<Item> with the self Iterator.

Extends buffer with as many elements of the iterator as taking specifies:

• RNone: Yields all elements.Use this with care, since Iterators can be infinite.

• RSome(n): Yields n elements.

Example

let mut wrapped = DynTrait::from_value(0..).interface(IteratorInterface::NEW);

let mut buffer = vec![101, 102, 103].into_c();
wrapped.extending_rvec(&mut buffer, RSome(5));
assert_eq!(&buffer[..], &*vec![101, 102, 103, 0, 1, 2, 3, 4]);

assert_eq!(wrapped.next(), Some(5));
assert_eq!(wrapped.next(), Some(6));
assert_eq!(wrapped.next(), Some(7));

impl<'borr, P, I, Item, EV> DynTrait<'borr, P, I, EV>

where Self: Iterator<Item = Item>, P: AsMutPtr, I: IteratorItemOrDefault<'borr, Item = Item> + InterfaceType<DoubleEndedIterator = Implemented<DoubleEndedIterator>>, Item: 'borr,

pub fn nth_back_(&mut self, nth: usize) -> Option<Item>

Gets teh nth element from the back of the iterator.

Example

use abi_stable::{erased_types::interfaces::DEIteratorCloneInterface, DynTrait};

let to = || DynTrait::from_value(7..=10).interface(DEIteratorCloneInterface::NEW);

assert_eq!(to().nth_back_(0), Some(10));
assert_eq!(to().nth_back_(1), Some(9));
assert_eq!(to().nth_back_(2), Some(8));
assert_eq!(to().nth_back_(3), Some(7));
assert_eq!(to().nth_back_(4), None);
assert_eq!(to().nth_back_(5), None);

pub fn extending_rvec_back( &mut self, buffer: &mut RVec<Item>, taking: ROption<usize>, )

Extends the RVec<Item> with the back of the self DoubleEndedIterator.

Extends buffer with as many elements of the iterator as taking specifies:

• RNone: Yields all elements.Use this with care, since Iterators can be infinite.

• RSome(n): Yields n elements.

Example

let mut wrapped = DynTrait::from_value(0..=3).interface(DEIteratorInterface::NEW);

let mut buffer = vec![101, 102, 103].into_c();
wrapped.extending_rvec_back(&mut buffer, RNone);
assert_eq!(&buffer[..], &*vec![101, 102, 103, 3, 2, 1, 0])

Trait Implementations

impl<'borr, P, I, EV> BufRead for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: InterfaceType<IoRead = Implemented<IoRead>, IoBufRead = Implemented<IoBufRead>>,

fn fill_buf(&mut self) -> Result<&[u8]>

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty.

fn consume(&mut self, amount: usize)

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to read.

fn has_data_left(&mut self) -> Result<bool, Error>

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

Checks if the underlying Read has any data left to be read.

fn read_until(&mut self, byte: u8, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes into buf until the delimiter byte or EOF is reached.

fn skip_until(&mut self, byte: u8) -> Result<usize, Error>

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

Skips all bytes until the delimiter byte or EOF is reached.

fn read_line(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until a newline (the 0xA byte) is reached, and append them to the provided String buffer.

fn split(self, byte: u8) -> Split<Self>

where Self: Sized,

Returns an iterator over the contents of this reader split on the byte byte.

fn lines(self) -> Lines<Self>

where Self: Sized,

Returns an iterator over the lines of this reader.

impl<'borr, P, I, EV> Clone for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType, Self: CloneImpl<<P as GetPointerKind>::Kind>,

Clone is implemented for references and smart pointers, using GetPointerKind to decide whether P is a smart pointer or a reference.

DynTrait does not implement Clone if P ==RMut<'_, ()> :

let mut object = DynTrait::from_value(()).interface(());
let borrow = object.reborrow_mut();
let _ = borrow.clone();

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'borr, P, I, EV> Debug for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType<Debug = Implemented<Debug>>,

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

Formats the value using the given formatter.

impl<'de, 'borr: 'de, P, I, EV> Deserialize<'de> for DynTrait<'borr, P, I, EV>

where EV: 'borr, P: AsPtr + 'borr, I: InterfaceType + 'borr + DeserializeDyn<'de, Self>, <I as DeserializeDyn<'de, Self>>::Proxy: Deserialize<'de>,

For an example of how to deserialize DynTrait, look here

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<'borr, P, I, EV> Display for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType<Display = Implemented<Display>>,

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

Formats the value using the given formatter.

impl<'borr, P, I, Item, EV> DoubleEndedIterator for DynTrait<'borr, P, I, EV>

where Self: Iterator<Item = Item>, P: AsMutPtr, I: IteratorItemOrDefault<'borr, Item = Item> + InterfaceType<DoubleEndedIterator = Implemented<DoubleEndedIterator>>, Item: 'borr,

fn next_back(&mut self) -> Option<Item>

Removes and returns an element from the end of the iterator.

fn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>

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

Advances the iterator from the back by n elements.

fn nth_back(&mut self, n: usize) -> Option<Self::Item>

Returns the nth element from the end of the iterator.

fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R

where Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Output = B>,

This is the reverse version of Iterator::try_fold(): it takes elements starting from the back of the iterator.

fn rfold<B, F>(self, init: B, f: F) -> B

where Self: Sized, F: FnMut(B, Self::Item) -> B,

An iterator method that reduces the iterator’s elements to a single, final value, starting from the back.

fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator from the back that satisfies a predicate.

impl<'borr, P, I, EV> Drop for DynTrait<'borr, P, I, EV>

where P: GetPointerKind,

fn drop(&mut self)

Executes the destructor for this type.

impl<'borr, P, I, EV> Error for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType<Display = Implemented<Display>, Debug = Implemented<Debug>, Error = Implemented<Error>>,

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

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

Provides type-based access to context intended for error reports.

impl<'borr, P, I, EV> GetStaticEquivalent_ for DynTrait<'borr, P, I, EV>

where P: GetPointerKind + __StableAbi, I: __StableAbi + InterfaceType, EV: __StableAbi, VTable_Ref<'borr, P, I>: StableAbi,

type StaticEquivalent = _static_DynTrait<'static, <P as GetStaticEquivalent_>::StaticEquivalent, <I as GetStaticEquivalent_>::StaticEquivalent, <EV as GetStaticEquivalent_>::StaticEquivalent>

The 'static equivalent of Self

impl<'borr, P, I, EV> Hash for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType<Hash = Implemented<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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<'borr, P, I, Item, EV> Iterator for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: IteratorItemOrDefault<'borr, Item = Item> + InterfaceType<Iterator = Implemented<Iterator>>, Item: 'borr,

type Item = Item

The type of the elements being iterated over.

fn next(&mut self) -> Option<Item>

Advances the iterator and returns the next value.

fn nth(&mut self, nth: usize) -> Option<Item>

Returns the nth element of the iterator.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn count(self) -> usize

Consumes the iterator, counting the number of iterations and returning it.

fn last(self) -> Option<Item>

Consumes the iterator, returning the last element.

fn next_chunk<const N: usize>( &mut self, ) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>

where Self: Sized,

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

Advances the iterator and returns an array containing the next N values.

fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>

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

Advances the iterator by n elements.

fn step_by(self, step: usize) -> StepBy<Self>

where Self: Sized,

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator<Item = Self::Item>,

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator,

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>

where Self: Sized, G: FnMut() -> Self::Item,

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

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

fn map<B, F>(self, f: F) -> Map<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> B,

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F)

where Self: Sized, F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator which uses a closure to determine if an element should be yielded.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>

where Self: Sized,

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>

where Self: Sized,

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>

where Self: Sized, P: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both yields elements based on a predicate and maps.

fn skip(self, n: usize) -> Skip<Self>

where Self: Sized,

Creates an iterator that skips the first n elements.

fn take(self, n: usize) -> Take<Self>

where Self: Sized,

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F>

where Self: Sized, F: FnMut(&mut St, Self::Item) -> Option<B>,

An iterator adapter which, like fold, holds internal state, but unlike fold, produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>

where Self: Sized, U: IntoIterator, F: FnMut(Self::Item) -> U,

Creates an iterator that works like map, but flattens nested structure.

fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>

where Self: Sized, F: FnMut(&[Self::Item; N]) -> R,

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

Calls the given function f for each contiguous window of size N over self and returns an iterator over the outputs of f. Like slice::windows(), the windows during mapping overlap as well.

fn fuse(self) -> Fuse<Self>

where Self: Sized,

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F>

where Self: Sized, F: FnMut(&Self::Item),

Does something with each element of an iterator, passing the value on.

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

where Self: Sized,

Borrows an iterator, rather than consuming it.

fn collect<B>(self) -> B

where B: FromIterator<Self::Item>, Self: Sized,

Transforms an iterator into a collection.

fn collect_into<E>(self, collection: &mut E) -> &mut E

where E: Extend<Self::Item>, Self: Sized,

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

Collects all the items from an iterator into a collection.

fn partition<B, F>(self, f: F) -> (B, B)

where Self: Sized, B: Default + Extend<Self::Item>, F: FnMut(&Self::Item) -> bool,

Consumes an iterator, creating two collections from it.

fn is_partitioned<P>(self, predicate: P) -> bool

where Self: Sized, P: FnMut(Self::Item) -> bool,

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

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R

where Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Output = B>,

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> R

where Self: Sized, F: FnMut(Self::Item) -> R, R: Try<Output = ()>,

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> B

where Self: Sized, F: FnMut(B, Self::Item) -> B,

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(Self::Item, Self::Item) -> Self::Item,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn try_reduce<R>( &mut self, f: impl FnMut(Self::Item, Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType

where Self: Sized, R: Try<Output = Self::Item>, <R as Try>::Residual: Residual<Option<Self::Item>>,

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

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately.

fn all<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator that satisfies a predicate.

fn find_map<B, F>(&mut self, f: F) -> Option<B>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<R>( &mut self, f: impl FnMut(&Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType

where Self: Sized, R: Try<Output = bool>, <R as Try>::Residual: Residual<Option<Self::Item>>,

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

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize>

where Self: Sized, P: FnMut(Self::Item) -> bool,

Searches for an element in an iterator, returning its index.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the maximum value with respect to the specified comparison function.

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the minimum value with respect to the specified comparison function.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)

where FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Sized + Iterator<Item = (A, B)>,

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self>

where T: 'a + Copy, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> Cloned<Self>

where T: 'a + Clone, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which clones all of its elements.

fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>

where Self: Sized,

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

Returns an iterator over N elements of the iterator at a time.

fn sum<S>(self) -> S

where Self: Sized, S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> P

where Self: Sized, P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

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

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Lexicographically compares the PartialOrd elements of this Iterator with those of another. The comparison works like short-circuit evaluation, returning a result without comparing the remaining elements. As soon as an order can be determined, the evaluation stops and a result is returned.

fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are equal to those of another.

fn eq_by<I, F>(self, other: I, eq: F) -> bool

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,

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

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are not equal to those of another.

fn lt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less or equal to those of another.

fn gt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another.

fn is_sorted_by<F>(self, compare: F) -> bool

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> bool,

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> K, K: PartialOrd,

Checks if the elements of this iterator are sorted using the given key extraction function.

impl<P, I, EV> Ord for DynTrait<'static, P, I, EV>

where P: AsPtr, I: InterfaceType<Ord = Implemented<Ord>>, Self: PartialOrd + Eq,

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

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl<P, P2, I, EV, EV2> PartialEq<DynTrait<'static, P2, I, EV2>> for DynTrait<'static, P, I, EV>

where P: AsPtr, P2: AsPtr, I: InterfaceType<PartialEq = Implemented<PartialEq>>,

fn eq(&self, other: &DynTrait<'static, P2, I, EV2>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<P, P2, I, EV, EV2> PartialOrd<DynTrait<'static, P2, I, EV2>> for DynTrait<'static, P, I, EV>

where P: AsPtr, P2: AsPtr, I: InterfaceType<PartialOrd = Implemented<PartialOrd>>, Self: PartialEq<DynTrait<'static, P2, I, EV2>>,

fn partial_cmp(&self, other: &DynTrait<'static, P2, I, EV2>) -> Option<Ordering>

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

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

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

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

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

impl<'borr, P, I, EV> Read for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: InterfaceType<IoRead = Implemented<IoRead>>,

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

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>

Reads the exact number of bytes required to fill buf.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

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

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

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

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

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

Reads the exact number of bytes required to fill cursor.

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

where Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

impl<'borr, P, I, EV> Seek for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: InterfaceType<IoSeek = Implemented<IoSeek>>,

fn seek(&mut self, pos: SeekFrom) -> Result<u64>

Seek to an offset, in bytes, in a stream.

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream.

fn stream_len(&mut self) -> Result<u64, Error>

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

Returns the length of this stream (in bytes).

fn stream_position(&mut self) -> Result<u64, Error>

Returns the current seek position from the start of the stream.

fn seek_relative(&mut self, offset: i64) -> Result<(), Error>

Seeks relative to the current position.

impl<'borr, P, I, EV> Serialize for DynTrait<'borr, P, I, EV>

where P: AsPtr, I: InterfaceType<Serialize = Implemented<Serialize>> + GetSerializeProxyType<'borr>, I::ProxyType: Serialize,

For an example of how to serialize DynTrait, look here

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

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<'borr, P, I, EV> StableAbi for DynTrait<'borr, P, I, EV>

where P: GetPointerKind + __StableAbi, I: __StableAbi + InterfaceType, EV: __StableAbi, VTable_Ref<'borr, P, I>: StableAbi,

type IsNonZeroType = False

Whether this type has a single invalid bit-pattern.

const LAYOUT: &'static TypeLayout = _

The layout of the type provided by implementors.

const ABI_CONSTS: AbiConsts = _

const-equivalents of the associated types.

impl<'borr, P, I, EV> Write for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: InterfaceType<FmtWrite = Implemented<FmtWrite>>,

fn write_str(&mut self, s: &str) -> Result<(), Error>

Writes a string slice into this writer, returning whether the write succeeded.

fn write_char(&mut self, c: char) -> Result<(), Error>

Writes a char into this writer, returning whether the write succeeded.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Glue for usage of the write! macro with implementors of this trait.

impl<'borr, P, I, EV> Write for DynTrait<'borr, P, I, EV>

where P: AsMutPtr, I: InterfaceType<IoWrite = Implemented<IoWrite>>,

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

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

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

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

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

Attempts to write an entire buffer into this writer.

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

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

fn is_write_vectored(&self) -> bool

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

Determines if this Writer has an efficient write_vectored implementation.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

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

Attempts to write multiple buffers into this writer.

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

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.

impl<P, I, EV> Eq for DynTrait<'static, P, I, EV>

where Self: PartialEq, P: AsPtr, I: InterfaceType<Eq = Implemented<Eq>>,

impl<'borr, P, I, EV> Send for DynTrait<'borr, P, I, EV>

where P: Send + GetPointerKind, I: InterfaceType<Send = Implemented<Send>>,

impl<'borr, P, I, EV> Sync for DynTrait<'borr, P, I, EV>

where P: Sync + GetPointerKind, I: InterfaceType<Sync = Implemented<Sync>>,

impl<'borr, P, I, EV> Unpin for DynTrait<'borr, P, I, EV>

where P: GetPointerKind, I: InterfaceType<Unpin = Implemented<Unpin>>,