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.

Trait Implementations§

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

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

1.0.0 · source§

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

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

1.0.0 · source§

fn lines(self) -> Lines<Self>
where Self: Sized,

Returns an iterator over the lines of this reader. Read more

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

fn clone(&self) -> Either<L, R> ⓘ

Returns a copy of the value. Read more

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

Reserves capacity in a collection for the given number of additional elements. Read more

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

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

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. 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_with<G>(self, separator: G) -> IntersperseWith<Self, G>
where Self: Sized, G: FnMut() -> Self::Item,

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

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 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 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)

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

1.6.0 · source§

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. Read more

1.15.0 · source§

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. Read more

1.6.0 · source§

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. Read more

1.15.0 · source§

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. Read more

1.0.0 · source§

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

Converts an iterator of pairs into a pair of containers. Read more

1.36.0 · source§

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. Read more

1.0.0 · source§

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. Read more

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. Read more

1.11.0 · source§

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.

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

Reads the exact number of bytes required to fill buf. Read more

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. Read more

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

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

1.36.0 · source§

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

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

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. Read more

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. Read more

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

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

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

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

1.55.0 · source§

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

Rewind to the beginning of a stream. Read more

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). Read more

1.51.0 · source§

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

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

1.80.0 · source§

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

Seeks relative to the current position. Read more

Visit a node of type YieldExpr. Read more

Visit a node of type WqName. Read more

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

Either<L, R> implements Write if both L and R do.

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

Determines if this Writer has an efficient write_vectored implementation. Read more

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. Read more

1.0.0 · source§

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

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

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

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>

fn try_as_bits<O>(&self) -> Result<&BitSlice<T, O>, BitSpanError<T>>
where O: BitOrder,

Attempts to view self as an immutable bit-slice region with the O ordering. Read more

impl<A, T> AsMutBits<T> for A
where A: AsMut<[T]>, T: BitStore,

fn as_mut_bits<O>(&mut self) -> &mut BitSlice<T, O> ⓘ
where O: BitOrder,

Views self as a mutable bit-slice region with the O ordering.

impl<T> From<T> for T

fn from(t: T) -> T

Returns the argument unchanged.

impl<It> IdentifyLast for It
where It: Iterator,

fn identify_last(self) -> Iter<It> ⓘ

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

fn clone_quote_var(&self) -> Self

Available on crate feature ecma_quote only.

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

👎Deprecated since 0.13.0: Use .chunk_by() instead

fn tree_reduce<F>(self, f: F) -> Option<Self::Item>
where F: FnMut(Self::Item, Self::Item) -> Self::Item, Self: Sized,

Accumulate the elements in the iterator in a tree-like manner. Read more

fn tree_fold1<F>(self, f: F) -> Option<Self::Item>
where F: FnMut(Self::Item, Self::Item) -> Self::Item, Self: Sized,

👎Deprecated since 0.13.0: Use .tree_reduce() instead

Apply a runtime-determined style

impl<T, P> Parse<Box<T>> for P
where P: Parse<T>,

fn parse(&mut self) -> Result<Box<T>, Error>

fn read_f64_into<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of IEEE754 double-precision (8 bytes) floating point numbers from the underlying reader. Read more

fn read_f64_into_unchecked<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

Calls .tap_deref_mut() only in debug builds, and is erased in release builds.

impl<T> ToHex for T
where T: AsRef<[u8]>,

fn encode_hex(&self) -> U
where U: FromIterator<char>,

Encode the hex strict representing self into the result. Lower case letters are used (e.g. f9b4ca)

fn encode_hex_upper(&self) -> U
where U: FromIterator<char>,

Encode the hex strict representing self into the result. Upper case letters are used (e.g. F9B4CA)

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

type Owned = T

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

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

Writes a IEEE754 double-precision (8 bytes) floating point number to the underlying writer. Read more

impl<T> ErasedDestructor for T
where T: 'static,

impl<T> MaybeSendSync for T

impl<N> NodeTrait for N
where N: Copy + Ord + Hash,