Enum Either Copy item path

Left(L)

A value of type L.

Right(R)

A value of type R.

Implementations§

impl<L, R> Either<L, R>

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 left(self) -> Option<L> ⓘ

Convert the left side of Either<L, R> to an Option<L>.

use either::*;

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

let right: Either<(), _> = Right(321);
assert_eq!(right.left(), None);

pub fn right(self) -> Option<R> ⓘ

Convert the right side of Either<L, R> to an Option<R>.

use either::*;

let left: Either<_, ()> = Left("some value");
assert_eq!(left.right(),  None);

let right: Either<(), _> = Right(321);
assert_eq!(right.right(), Some(321));

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 flip(self) -> Either<R, L> ⓘ

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

use either::*;

let left: Either<_, ()> = Left(123);
assert_eq!(left.flip(), Right(123));

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

pub fn map_left<F, M>(self, f: F) -> Either<M, R> ⓘ
where F: FnOnce(L) -> M,

Apply the function f on the value in the Left variant if it is present rewrapping the result in Left.

use either::*;

let left: Either<_, u32> = Left(123);
assert_eq!(left.map_left(|x| x * 2), Left(246));

let right: Either<u32, _> = Right(123);
assert_eq!(right.map_left(|x| x * 2), Right(123));

pub fn map_right<F, S>(self, f: F) -> Either<L, S> ⓘ
where F: FnOnce(R) -> S,

Apply the function f on the value in the Right variant if it is present rewrapping the result in Right.

use either::*;

let left: Either<_, u32> = Left(123);
assert_eq!(left.map_right(|x| x * 2), Left(123));

let right: Either<u32, _> = Right(123);
assert_eq!(right.map_right(|x| x * 2), Right(246));

pub fn map_either<F, G, M, S>(self, f: F, g: G) -> Either<M, S> ⓘ
where F: FnOnce(L) -> M, G: FnOnce(R) -> S,

Apply the functions f and g to the Left and Right variants respectively. This is equivalent to bimap in functional programming.

use either::*;

let f = |s: String| s.len();
let g = |u: u8| u.to_string();

let left: Either<String, u8> = Left("loopy".into());
assert_eq!(left.map_either(f, g), Left(5));

let right: Either<String, u8> = Right(42);
assert_eq!(right.map_either(f, g), Right("42".into()));

pub fn map_either_with<Ctx, F, G, M, S>( self, ctx: Ctx, f: F, g: G, ) -> Either<M, S> ⓘ
where F: FnOnce(Ctx, L) -> M, G: FnOnce(Ctx, R) -> S,

Similar to map_either, with an added context ctx accessible to both functions.

use either::*;

let mut sum = 0;

// Both closures want to update the same value, so pass it as context.
let mut f = |sum: &mut usize, s: String| { *sum += s.len(); s.to_uppercase() };
let mut g = |sum: &mut usize, u: usize| { *sum += u; u.to_string() };

let left: Either<String, usize> = Left("loopy".into());
assert_eq!(left.map_either_with(&mut sum, &mut f, &mut g), Left("LOOPY".into()));

let right: Either<String, usize> = Right(42);
assert_eq!(right.map_either_with(&mut sum, &mut f, &mut g), Right("42".into()));

assert_eq!(sum, 47);

pub fn either<F, G, T>(self, f: F, g: G) -> T
where F: FnOnce(L) -> T, G: FnOnce(R) -> T,

Apply one of two functions depending on contents, unifying their result. If the value is Left(L) then the first function f is applied; if it is Right(R) then the second function g is applied.

use either::*;

fn square(n: u32) -> i32 { (n * n) as i32 }
fn negate(n: i32) -> i32 { -n }

let left: Either<u32, i32> = Left(4);
assert_eq!(left.either(square, negate), 16);

let right: Either<u32, i32> = Right(-4);
assert_eq!(right.either(square, negate), 4);

pub fn either_with<Ctx, F, G, T>(self, ctx: Ctx, f: F, g: G) -> T
where F: FnOnce(Ctx, L) -> T, G: FnOnce(Ctx, R) -> T,

Like either, but provide some context to whichever of the functions ends up being called.

// In this example, the context is a mutable reference
use either::*;

let mut result = Vec::new();

let values = vec![Left(2), Right(2.7)];

for value in values {
    value.either_with(&mut result,
                      |ctx, integer| ctx.push(integer),
                      |ctx, real| ctx.push(f64::round(real) as i32));
}

assert_eq!(result, vec![2, 3]);

pub fn left_and_then<F, S>(self, f: F) -> Either<S, R> ⓘ
where F: FnOnce(L) -> Either<S, R>,

Apply the function f on the value in the Left variant if it is present.

use either::*;

let left: Either<_, u32> = Left(123);
assert_eq!(left.left_and_then::<_,()>(|x| Right(x * 2)), Right(246));

let right: Either<u32, _> = Right(123);
assert_eq!(right.left_and_then(|x| Right::<(), _>(x * 2)), Right(123));

pub fn right_and_then<F, S>(self, f: F) -> Either<L, S> ⓘ
where F: FnOnce(R) -> Either<L, S>,

Apply the function f on the value in the Right variant if it is present.

use either::*;

let left: Either<_, u32> = Left(123);
assert_eq!(left.right_and_then(|x| Right(x * 2)), Left(123));

let right: Either<u32, _> = Right(123);
assert_eq!(right.right_and_then(|x| Right(x * 2)), Right(246));

pub fn into_iter( self, ) -> Either<<L as IntoIterator>::IntoIter, <R as IntoIterator>::IntoIter> ⓘ
where L: IntoIterator, R: IntoIterator<Item = <L as IntoIterator>::Item>,

Convert the inner value to an iterator.

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

use either::*;

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

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_into_iter( self, ) -> IterEither<<L as IntoIterator>::IntoIter, <R as IntoIterator>::IntoIter> ⓘ
where L: IntoIterator, R: IntoIterator,

Converts an Either of Iterators to be an Iterator of Eithers

Unlike into_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_into_iter().next(), Some(Left(&"hello")));
let right: Either<&[&str], _> = Right(vec![0, 1]);
assert_eq!(right.factor_into_iter().collect::<Vec<_>>(), vec![Right(0), Right(1)]);

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]));

pub fn left_or(self, other: L) -> L

Return left value or given value

Arguments passed to left_or are eagerly evaluated; if you are passing the result of a function call, it is recommended to use left_or_else, which is lazily evaluated.

§Examples

let left: Either<&str, &str> = Left("left");
assert_eq!(left.left_or("foo"), "left");

let right: Either<&str, &str> = Right("right");
assert_eq!(right.left_or("left"), "left");

pub fn left_or_default(self) -> L
where L: Default,

Return left or a default

§Examples

let left: Either<String, u32> = Left("left".to_string());
assert_eq!(left.left_or_default(), "left");

let right: Either<String, u32> = Right(42);
assert_eq!(right.left_or_default(), String::default());

pub fn left_or_else<F>(self, f: F) -> L
where F: FnOnce(R) -> L,

Returns left value or computes it from a closure

§Examples

let left: Either<String, u32> = Left("3".to_string());
assert_eq!(left.left_or_else(|_| unreachable!()), "3");

let right: Either<String, u32> = Right(3);
assert_eq!(right.left_or_else(|x| x.to_string()), "3");

pub fn right_or(self, other: R) -> R

Return right value or given value

Arguments passed to right_or are eagerly evaluated; if you are passing the result of a function call, it is recommended to use right_or_else, which is lazily evaluated.

§Examples

let right: Either<&str, &str> = Right("right");
assert_eq!(right.right_or("foo"), "right");

let left: Either<&str, &str> = Left("left");
assert_eq!(left.right_or("right"), "right");

pub fn right_or_default(self) -> R
where R: Default,

Return right or a default

§Examples

let left: Either<String, u32> = Left("left".to_string());
assert_eq!(left.right_or_default(), u32::default());

let right: Either<String, u32> = Right(42);
assert_eq!(right.right_or_default(), 42);

pub fn right_or_else<F>(self, f: F) -> R
where F: FnOnce(L) -> R,

Returns right value or computes it from a closure

§Examples

let left: Either<String, u32> = Left("3".to_string());
assert_eq!(left.right_or_else(|x| x.parse().unwrap()), 3);

let right: Either<String, u32> = Right(3);
assert_eq!(right.right_or_else(|_| unreachable!()), 3);

pub fn unwrap_left(self) -> L
where R: Debug,

Returns the left value

§Examples

let left: Either<_, ()> = Left(3);
assert_eq!(left.unwrap_left(), 3);

§Panics

When Either is a Right value

let right: Either<(), _> = Right(3);
right.unwrap_left();

pub fn unwrap_right(self) -> R
where L: Debug,

Returns the right value

§Examples

let right: Either<(), _> = Right(3);
assert_eq!(right.unwrap_right(), 3);

§Panics

When Either is a Left value

let left: Either<_, ()> = Left(3);
left.unwrap_right();

pub fn expect_left(self, msg: &str) -> L
where R: Debug,

Returns the left value

§Examples

let left: Either<_, ()> = Left(3);
assert_eq!(left.expect_left("value was Right"), 3);

§Panics

When Either is a Right value

let right: Either<(), _> = Right(3);
right.expect_left("value was Right");

pub fn expect_right(self, msg: &str) -> R
where L: Debug,

Returns the right value

§Examples

let right: Either<(), _> = Right(3);
assert_eq!(right.expect_right("value was Left"), 3);

§Panics

When Either is a Left value

let left: Either<_, ()> = Left(3);
left.expect_right("value was Right");

pub fn either_into<T>(self) -> T
where L: Into<T>, R: Into<T>,

Convert the contained value into T

§Examples

// Both u16 and u32 can be converted to u64.
let left: Either<u16, u32> = Left(3u16);
assert_eq!(left.either_into::<u64>(), 3u64);
let right: Either<u16, u32> = Right(7u32);
assert_eq!(right.either_into::<u64>(), 7u64);

impl<L, R> Either<Option<L>, Option<R>>

pub fn factor_none(self) -> Option<Either<L, R>> ⓘ

Factors out None from an Either of Option.

use either::*;
let left: Either<_, Option<String>> = Left(Some(vec![0]));
assert_eq!(left.factor_none(), Some(Left(vec![0])));

let right: Either<Option<Vec<u8>>, _> = Right(Some(String::new()));
assert_eq!(right.factor_none(), Some(Right(String::new())));

impl<L, R, E> Either<Result<L, E>, Result<R, E>>

pub fn factor_err(self) -> Result<Either<L, R>, E> ⓘ

Factors out a homogenous type from an Either of Result.

Here, the homogeneous type is the Err type of the Result.

use either::*;
let left: Either<_, Result<String, u32>> = Left(Ok(vec![0]));
assert_eq!(left.factor_err(), Ok(Left(vec![0])));

let right: Either<Result<Vec<u8>, u32>, _> = Right(Ok(String::new()));
assert_eq!(right.factor_err(), Ok(Right(String::new())));

impl<T, L, R> Either<Result<T, L>, Result<T, R>>

pub fn factor_ok(self) -> Result<T, Either<L, R>> ⓘ

Factors out a homogenous type from an Either of Result.

Here, the homogeneous type is the Ok type of the Result.

use either::*;
let left: Either<_, Result<u32, String>> = Left(Err(vec![0]));
assert_eq!(left.factor_ok(), Err(Left(vec![0])));

let right: Either<Result<u32, Vec<u8>>, _> = Right(Err(String::new()));
assert_eq!(right.factor_ok(), Err(Right(String::new())));

impl<T, L, R> Either<(T, L), (T, R)>

pub fn factor_first(self) -> (T, Either<L, R>) ⓘ

Factor out a homogeneous type from an either of pairs.

Here, the homogeneous type is the first element of the pairs.

use either::*;
let left: Either<_, (u32, String)> = Left((123, vec![0]));
assert_eq!(left.factor_first().0, 123);

let right: Either<(u32, Vec<u8>), _> = Right((123, String::new()));
assert_eq!(right.factor_first().0, 123);

impl<T, L, R> Either<(L, T), (R, T)>

pub fn factor_second(self) -> (Either<L, R>, T) ⓘ

Factor out a homogeneous type from an either of pairs.

Here, the homogeneous type is the second element of the pairs.

use either::*;
let left: Either<_, (String, u32)> = Left((vec![0], 123));
assert_eq!(left.factor_second().1, 123);

let right: Either<(Vec<u8>, u32), _> = Right((String::new(), 123));
assert_eq!(right.factor_second().1, 123);

pub fn copied(self) -> Either<L, R> ⓘ
where L: Copy, R: Copy,

Maps an Either<&L, &R> to an Either<L, R> by copying the contents of either branch.

impl<L, R> Either<&mut L, &mut R>

pub fn cloned(self) -> Either<L, R> ⓘ
where L: Clone, R: Clone,

Maps an Either<&mut L, &mut R> to an Either<L, R> by cloning the contents of either branch.

pub fn copied(self) -> Either<L, R> ⓘ
where L: Copy, R: Copy,

Maps an Either<&mut L, &mut R> to an Either<L, R> by copying the contents of either branch.

Returns a copy of the value. Read more

fn rfold<Acc, G>(self, init: Acc, f: G) -> Acc
where G: FnMut(Acc, <Either<L, R> as Iterator>::Item) -> Acc,

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

fn rfind(&mut self, predicate: P) -> Option<<Either<L, R> as Iterator>::Item> ⓘ
where P: FnMut(&<Either<L, R> as Iterator>::Item) -> bool,

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

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. Read more

1.27.0 · Source§

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. Read more

impl<L, R> ExactSizeIterator for Either<L, R>
where L: ExactSizeIterator, R: ExactSizeIterator<Item = <L as Iterator>::Item>,

fn len(&self) -> usize ⓘ

Returns the exact remaining length of the iterator. Read more

fn is_empty(&self) -> bool

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

Returns true if the iterator is empty. Read more

impl<L, R, A> Extend<A> for Either<L, R>
where L: Extend<A>, R: Extend<A>,

Convert from Result to Either with Ok => Right and Err => Left.

fn from(r: Result<R, L>) -> Either<L, R> ⓘ

Converts to this type from the input type.

impl<L, R, A, B> FromParallelIterator<Either<L, R>> for (A, B)
where L: Send, R: Send, A: Send + FromParallelIterator<L>, B: Send + FromParallelIterator<R>,

fn from_par_iter(pi: I) -> (A, B) ⓘ
where I: IntoParallelIterator<Item = Either<L, R>>,

Creates an instance of the collection from the parallel iterator par_iter. Read more

impl<L, R> Future for Either<L, R>
where L: Future, R: Future<Output = <L as Future>::Output>,

Either<L, R> is a future if both L and R are futures.

type Output = <L as Future>::Output

The type of value produced on completion.

fn poll( self: Pin<&mut Either<L, R>>, cx: &mut Context<'_>, ) -> Poll<<Either<L, R> as Future>::Output>

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

impl<L, R> Hash for Either<L, R>
where L: Hash, R: Hash,

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

Feeds this value into the given Hasher. Read more

1.3.0 · Source§

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

Feeds a slice of this type into the given Hasher. Read more

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

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

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. Read more

1.28.0 · Source§

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. Read more

1.0.0 · Source§

fn chain(self, other: U) -> Chain<Self, ::IntoIter> ⓘ
where Self: Sized, U: IntoIterator<Item = Self::Item>,

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

1.0.0 · Source§

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

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

fn intersperse(self, separator: Self::Item) -> Intersperse<Self> ⓘ
where Self: Sized, Self::Item: Clone,

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

Creates a new iterator which places a copy of separator between adjacent items of the original iterator. Read more

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)

🔬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. Read more

1.0.0 · Source§

fn fuse(self) -> Fuse<Self> ⓘ
where Self: Sized,

Creates an iterator which ends after the first None. Read more

1.0.0 · Source§

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. Read more

1.0.0 · Source§

fn by_ref(&mut self) -> &mut Self
where Self: Sized,

Borrows an iterator, rather than consuming it. Read more

fn try_collect( &mut self, ) -> <<Self::Item as Try>::Residual as Residual>::TryType
where Self: Sized, Self::Item: Try, <Self::Item as Try>::Residual: Residual, B: FromIterator<<Self::Item as Try>::Output>,

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

Fallibly transforms an iterator into a collection, short circuiting if a failure is encountered. Read more

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. Read more

fn partition_in_place<'a, T, P>(self, predicate: P) -> usize ⓘ
where T: 'a, Self: Sized + DoubleEndedIterator<Item = &'a mut T>, P: FnMut(&T) -> bool,

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

Reorders the elements of this iterator in-place according to the given predicate, such that all those that return true precede all those that return false. Returns the number of true elements found. Read more

fn is_partitioned(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. Read more

1.27.0 · Source§

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. Read more

1.27.0 · Source§

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. Read more

1.51.0 · Source§

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. Read more

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. Read more

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)

fn sum<S>(self) -> S
where Self: Sized, S: Sum<Self::Item>,

Sums the elements of an iterator. Read more

1.11.0 · Source§

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

impl<L, R> Ord for Either<L, R>
where L: Ord, R: Ord,

fn cmp(&self, other: &Either<L, R>) -> Ordering

This method returns an Ordering between self and other. Read more

1.21.0 · Source§

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

Compares and returns the maximum of two values. Read more

1.21.0 · Source§

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

Compares and returns the minimum of two values. Read more

1.50.0 · Source§

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

Restrict a value to a certain interval. Read more

Collects this iterator into a linked list of vectors. Read more

impl<L, R> PartialEq for Either<L, R>
where L: PartialEq, R: PartialEq,

fn eq(&self, other: &Either<L, R>) -> bool

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

1.0.0 · Source§

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<L, R> Eq for Either<L, R>
where L: Eq, R: Eq,

impl<L, R> FusedIterator for Either<L, R>
where L: FusedIterator, R: FusedIterator<Item = <L as Iterator>::Item>,

impl<L, R> StructuralPartialEq for Either<L, R>

Auto Trait Implementations§

The archived version of the pointer metadata for this type.

The size of this type in bytes.

fn byte_align(&self) -> usize ⓘ

Returns the alignment of this type in bytes.

fn byte_size(&self) -> usize ⓘ

Returns the size of this type in bytes. Read more

fn ptr_size_ratio(&self) -> [usize; 2]

Returns the size ratio between Ptr::BYTES and BYTE_SIZE. Read more

impl<T, R> Chain<R> for T
where T: ?Sized,

fn chain<F>(self, f: F) -> R
where F: FnOnce(Self) -> R, Self: Sized,

Chain a function which takes the parameter by value.

fn chain_ref<F>(&self, f: F) -> R
where F: FnOnce(&Self) -> R,

Chain a function which takes the parameter by shared reference.

fn chain_mut<F>(&mut self, f: F) -> R
where F: FnOnce(&mut Self) -> R,

Chain a function which takes the parameter by exclusive reference.

impl<T> CloneToUninit for T
where T: Clone,

unsafe fn clone_to_uninit(&self, dst: *mut u8)

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

fn type_name(&self) -> &'static str ⓘ

Returns the type name of self. Read more

fn type_is<T: 'static>(&self) -> bool

Returns true if Self is of type T. Read more

fn as_any_ref(&self) -> &dyn Any
where Self: Sized,

Upcasts &self as &dyn Any. Read more

fn as_any_mut(&mut self) -> &mut dyn Any
where Self: Sized,

Upcasts &mut self as &mut dyn Any. Read more

fn block_on(self) -> Self::Output
where Self: Sized,

Available on crate feature std only.

Blocks the thread until the future is ready. Read more

fn from(t: T) -> T

Returns the argument unchanged.

impl<S> FromSample<S> for S

fn from_sample_(s: S) -> S

impl<T> Hook for T

fn hook_ref<F>(self, f: F) -> Self
where F: FnOnce(&Self),

Applies a function which takes the parameter by shared reference, and then returns the (possibly) modified owned value. Read more

fn hook_mut<F>(self, f: F) -> Self
where F: FnOnce(&mut Self),

Applies a function which takes the parameter by exclusive reference, and then returns the (possibly) modified owned value. Read more

impl<T> Instrument for T

fn instrument(self, span: Span) -> Instrumented<Self> ⓘ

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

fn in_current_span(self) -> Instrumented<Self> ⓘ

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

impl<F, T> IntoSample<T> for F
where T: FromSample<F>,

Returns whether the given value has been niched. Read more

fn resolve_niched(out: Place<NichedOption<T, N1>>)

Writes data to out indicating that a T is niched.

Drops the object pointed to by the given pointer. Read more

impl<T> Pointee for T

type Metadata = ()

The metadata type for pointers and references to this type.

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more

impl<T, U> ToSample for T
where U: FromSample<T>,

fn to_sample_(self) -> U