Struct EitherFuture

pub struct EitherFuture<Left, Right>(pub Either<Left, Right>);

Tuple Fields

0: Either<Left, Right>

Implementations

impl<Left, Right> EitherFuture<Left, Right>

pub fn left(left_future: Left) -> Self

pub fn right(right_future: Right) -> Self

Methods from Deref<Target = Either<Left, Right>>

pub fn is_left(&self) -> bool

Return true if the value is the Left variant.

use either::*;

let values = [Left(1), Right("the right value")];
assert_eq!(values[0].is_left(), true);
assert_eq!(values[1].is_left(), false);

pub fn is_right(&self) -> bool

Return true if the value is the Right variant.

use either::*;

let values = [Left(1), Right("the right value")];
assert_eq!(values[0].is_right(), false);
assert_eq!(values[1].is_right(), true);

pub fn as_ref(&self) -> Either<&L, &R>

Convert &Either<L, R> to Either<&L, &R>.

use either::*;

let left: Either<_, ()> = Left("some value");
assert_eq!(left.as_ref(), Left(&"some value"));

let right: Either<(), _> = Right("some value");
assert_eq!(right.as_ref(), Right(&"some value"));

pub fn as_mut(&mut self) -> Either<&mut L, &mut R>

Convert &mut Either<L, R> to Either<&mut L, &mut R>.

use either::*;

fn mutate_left(value: &mut Either<u32, u32>) {
    if let Some(l) = value.as_mut().left() {
        *l = 999;
    }
}

let mut left = Left(123);
let mut right = Right(123);
mutate_left(&mut left);
mutate_left(&mut right);
assert_eq!(left, Left(999));
assert_eq!(right, Right(123));

pub fn as_pin_ref(self: Pin<&Either<L, R>>) -> Either<Pin<&L>, Pin<&R>>

Convert Pin<&Either<L, R>> to Either<Pin<&L>, Pin<&R>>, pinned projections of the inner variants.

pub fn as_pin_mut( self: Pin<&mut Either<L, R>>, ) -> Either<Pin<&mut L>, Pin<&mut R>>

Convert Pin<&mut Either<L, R>> to Either<Pin<&mut L>, Pin<&mut R>>, pinned projections of the inner variants.

pub fn iter( &self, ) -> Either<<&L as IntoIterator>::IntoIter, <&R as IntoIterator>::IntoIter>

where &'a L: for<'a> IntoIterator, &'a R: for<'a> IntoIterator<Item = <&'a L as IntoIterator>::Item>,

Borrow the inner value as an iterator.

This requires the Left and Right iterators to have the same item type. See factor_iter to iterate different types.

use either::*;

let left: Either<_, &[u32]> = Left(vec![2, 3]);
let mut right: Either<Vec<u32>, _> = Right(&[4, 5][..]);
let mut all = vec![1];
all.extend(left.iter());
all.extend(right.iter());
assert_eq!(all, vec![1, 2, 3, 4, 5]);

pub fn iter_mut( &mut self, ) -> Either<<&mut L as IntoIterator>::IntoIter, <&mut R as IntoIterator>::IntoIter>

where &'a mut L: for<'a> IntoIterator, &'a mut R: for<'a> IntoIterator<Item = <&'a mut L as IntoIterator>::Item>,

Mutably borrow the inner value as an iterator.

This requires the Left and Right iterators to have the same item type. See factor_iter_mut to iterate different types.

use either::*;

let mut left: Either<_, &mut [u32]> = Left(vec![2, 3]);
for l in left.iter_mut() {
    *l *= *l
}
assert_eq!(left, Left(vec![4, 9]));

let mut inner = [4, 5];
let mut right: Either<Vec<u32>, _> = Right(&mut inner[..]);
for r in right.iter_mut() {
    *r *= *r
}
assert_eq!(inner, [16, 25]);

pub fn factor_iter( &self, ) -> IterEither<<&L as IntoIterator>::IntoIter, <&R as IntoIterator>::IntoIter>

where &'a L: for<'a> IntoIterator, &'a R: for<'a> IntoIterator,

Borrows an Either of Iterators to be an Iterator of Eithers

Unlike iter, this does not require the Left and Right iterators to have the same item type.

use either::*;
let left: Either<_, Vec<u8>> = Left(["hello"]);
assert_eq!(left.factor_iter().next(), Some(Left(&"hello")));

let right: Either<[&str; 2], _> = Right(vec![0, 1]);
assert_eq!(right.factor_iter().collect::<Vec<_>>(), vec![Right(&0), Right(&1)]);

pub fn factor_iter_mut( &mut self, ) -> IterEither<<&mut L as IntoIterator>::IntoIter, <&mut R as IntoIterator>::IntoIter>

where &'a mut L: for<'a> IntoIterator, &'a mut R: for<'a> IntoIterator,

Mutably borrows an Either of Iterators to be an Iterator of Eithers

Unlike iter_mut, this does not require the Left and Right iterators to have the same item type.

use either::*;
let mut left: Either<_, Vec<u8>> = Left(["hello"]);
left.factor_iter_mut().for_each(|x| *x.unwrap_left() = "goodbye");
assert_eq!(left, Left(["goodbye"]));

let mut right: Either<[&str; 2], _> = Right(vec![0, 1, 2]);
right.factor_iter_mut().for_each(|x| if let Right(r) = x { *r = -*r; });
assert_eq!(right, Right(vec![0, -1, -2]));

Trait Implementations

impl<Left, Right> Deref for EitherFuture<Left, Right>

type Target = Either<Left, Right>

The resulting type after dereferencing.

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

Dereferences the value.

impl<Left, Right> DerefMut for EitherFuture<Left, Right>

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

Mutably dereferences the value.

impl<Left, Right> From<Either<Left, Right>> for EitherFuture<Left, Right>

fn from(either: Either<Left, Right>) -> Self

Converts to this type from the input type.

impl<LeftFuture, RightFuture> From<Either<LeftFuture, RightFuture>> for EitherFuture<LeftFuture, RightFuture>

fn from(either: Either<LeftFuture, RightFuture>) -> Self

Converts to this type from the input type.

impl<Left, Right> From<EitherFuture<Left, Right>> for Either<Left, Right>

fn from(either_future: EitherFuture<Left, Right>) -> Either<Left, Right>

Converts to this type from the input type.

impl<LeftFuture, RightFuture> From<EitherFuture<LeftFuture, RightFuture>> for Either<LeftFuture, RightFuture>

fn from(either_future: EitherFuture<LeftFuture, RightFuture>) -> Self

Converts to this type from the input type.

impl<Left, Right, LeftFuture, RightFuture> Future for EitherFuture<LeftFuture, RightFuture>

where LeftFuture: Future<Output = Left>, RightFuture: Future<Output = Right>,

type Output = Either<Left, Right>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, context: &mut Context<'_>) -> Poll<Self::Output>

Attempts to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<Left, Right, ErrorType, LeftFuture, RightFuture> Future for EitherFuture<LeftFuture, RightFuture>

where LeftFuture: Future<Item = Left, Error = ErrorType>, RightFuture: Future<Item = Right, Error = ErrorType>,

type Item = Either<Left, Right>

The type of value that this future will resolved with if it is successful.

type Error = ErrorType

The type of error that this future will resolve with if it fails in a normal fashion.

fn poll(&mut self) -> Result<Async<Self::Item>, Self::Error>

Query this future to see if its value has become available, registering interest if it is not.

fn wait(self) -> Result<Self::Item, Self::Error>

where Self: Sized,

Block the current thread until this future is resolved.

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

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

Map this future’s result to a different type, returning a new future of the resulting type.

fn map_err<F, E>(self, f: F) -> MapErr<Self, F>

where F: FnOnce(Self::Error) -> E, Self: Sized,

Map this future’s error to a different error, returning a new future.

fn from_err<E>(self) -> FromErr<Self, E>

where E: From<Self::Error>, Self: Sized,

Map this future’s error to any error implementing From for this future’s Error, returning a new future.

fn then<F, B>(self, f: F) -> Then<Self, B, F>

where F: FnOnce(Result<Self::Item, Self::Error>) -> B, B: IntoFuture, Self: Sized,

Chain on a computation for when a future finished, passing the result of the future to the provided closure f.

fn and_then<F, B>(self, f: F) -> AndThen<Self, B, F>

where F: FnOnce(Self::Item) -> B, B: IntoFuture<Error = Self::Error>, Self: Sized,

Execute another future after this one has resolved successfully.

fn or_else<F, B>(self, f: F) -> OrElse<Self, B, F>

where F: FnOnce(Self::Error) -> B, B: IntoFuture<Item = Self::Item>, Self: Sized,

Execute another future if this one resolves with an error.

fn select<B>(self, other: B) -> Select<Self, <B as IntoFuture>::Future>

where B: IntoFuture<Item = Self::Item, Error = Self::Error>, Self: Sized,

Waits for either one of two futures to complete.

fn select2<B>(self, other: B) -> Select2<Self, <B as IntoFuture>::Future>

where B: IntoFuture, Self: Sized,

Waits for either one of two differently-typed futures to complete.

fn join<B>(self, other: B) -> Join<Self, <B as IntoFuture>::Future>

where B: IntoFuture<Error = Self::Error>, Self: Sized,

Joins the result of two futures, waiting for them both to complete.

fn join3<B, C>( self, b: B, c: C, ) -> Join3<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future>

where B: IntoFuture<Error = Self::Error>, C: IntoFuture<Error = Self::Error>, Self: Sized,

Same as join, but with more futures.

fn join4<B, C, D>( self, b: B, c: C, d: D, ) -> Join4<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future>

where B: IntoFuture<Error = Self::Error>, C: IntoFuture<Error = Self::Error>, D: IntoFuture<Error = Self::Error>, Self: Sized,

Same as join, but with more futures.

fn join5<B, C, D, E>( self, b: B, c: C, d: D, e: E, ) -> Join5<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future, <E as IntoFuture>::Future>

where B: IntoFuture<Error = Self::Error>, C: IntoFuture<Error = Self::Error>, D: IntoFuture<Error = Self::Error>, E: IntoFuture<Error = Self::Error>, Self: Sized,

Same as join, but with more futures.

fn into_stream(self) -> IntoStream<Self>

where Self: Sized,

Convert this future into a single element stream.

fn flatten(self) -> Flatten<Self>

where Self::Item: IntoFuture, <Self::Item as IntoFuture>::Error: From<Self::Error>, Self: Sized,

Flatten the execution of this future when the successful result of this future is itself another future.

fn flatten_stream(self) -> FlattenStream<Self>

where Self::Item: Stream<Error = Self::Error>, Self: Sized,

Flatten the execution of this future when the successful result of this future is a stream.

fn fuse(self) -> Fuse<Self>

where Self: Sized,

Fuse a future such that poll will never again be called once it has completed.

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

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

Do something with the item of a future, passing it on.

fn catch_unwind(self) -> CatchUnwind<Self>

where Self: Sized + UnwindSafe,

Catches unwinding panics while polling the future.

fn shared(self) -> Shared<Self>

where Self: Sized,

Create a cloneable handle to this future where all handles will resolve to the same result.