pub enum Either<L, R> {
Left(L),
Right(R),
}
Expand description
The enum Either
with variants Left
and Right
is a general purpose
sum type with two cases.
The Either
type is symmetric and treats its variants the same way, without
preference.
(For representing success or error, use the regular Result
enum instead.)
Variants
Left(L)
A value of type L
.
Right(R)
A value of type R
.
Implementations
sourceimpl<L, R> Either<L, R>
impl<L, R> Either<L, R>
sourcepub fn is_left(&self) -> bool
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);
sourcepub fn is_right(&self) -> bool
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);
sourcepub fn left(self) -> Option<L>
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);
sourcepub fn right(self) -> Option<R>
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));
sourcepub fn as_ref(&self) -> Either<&L, &R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
pub fn as_ref(&self) -> Either<&L, &R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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"));
sourcepub fn as_mut(&mut self) -> Either<&mut L, &mut R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
pub fn as_mut(&mut self) -> Either<&mut L, &mut R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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));
sourcepub fn flip(self) -> Either<R, L>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
pub fn flip(self) -> Either<R, L>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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"));
sourcepub fn map_left<F, M>(self, f: F) -> Either<M, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(L) -> M,
pub fn map_left<F, M>(self, f: F) -> Either<M, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(L) -> M,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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));
sourcepub fn map_right<F, S>(self, f: F) -> Either<L, S>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(R) -> S,
pub fn map_right<F, S>(self, f: F) -> Either<L, S>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(R) -> S,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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));
sourcepub fn either<F, G, T>(self, f: F, g: G) -> T where
F: FnOnce(L) -> T,
G: FnOnce(R) -> T,
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);
sourcepub 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,
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]);
sourcepub fn left_and_then<F, S>(self, f: F) -> Either<S, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(L) -> Either<S, R>,
pub fn left_and_then<F, S>(self, f: F) -> Either<S, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(L) -> Either<S, R>,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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));
sourcepub fn right_and_then<F, S>(self, f: F) -> Either<L, S>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(R) -> Either<L, S>,
pub fn right_and_then<F, S>(self, f: F) -> Either<L, S>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(R) -> Either<L, S>,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
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));
sourcepub fn into_iter(self) -> Either<L::IntoIter, R::IntoIter>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
L: IntoIterator,
R: IntoIterator<Item = L::Item>,
pub fn into_iter(self) -> Either<L::IntoIter, R::IntoIter>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
L: IntoIterator,
R: IntoIterator<Item = L::Item>,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
Convert the inner value to an iterator.
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]));
sourcepub fn left_or(self, other: L) -> L
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");
sourcepub fn left_or_default(self) -> L where
L: Default,
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());
sourcepub fn left_or_else<F>(self, f: F) -> L where
F: FnOnce(R) -> L,
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");
sourcepub fn right_or(self, other: R) -> R
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");
sourcepub fn right_or_default(self) -> R where
R: Default,
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);
sourcepub fn right_or_else<F>(self, f: F) -> R where
F: FnOnce(L) -> R,
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);
sourcepub fn unwrap_left(self) -> L where
R: Debug,
pub fn unwrap_left(self) -> L where
R: Debug,
sourcepub fn unwrap_right(self) -> R where
L: Debug,
pub fn unwrap_right(self) -> R where
L: Debug,
sourcepub fn expect_left(self, msg: &str) -> L where
R: Debug,
pub fn expect_left(self, msg: &str) -> L where
R: Debug,
sourceimpl<T, L, R> Either<(T, L), (T, R)>
impl<T, L, R> Either<(T, L), (T, R)>
sourcepub fn factor_first(self) -> (T, Either<L, 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);
sourceimpl<T, L, R> Either<(L, T), (R, T)>
impl<T, L, R> Either<(L, T), (R, T)>
sourcepub fn factor_second(self) -> (Either<L, 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);
sourceimpl<T> Either<T, T>
impl<T> Either<T, T>
sourcepub fn into_inner(self) -> T
pub fn into_inner(self) -> T
Extract the value of an either over two equivalent types.
use either::*;
let left: Either<_, u32> = Left(123);
assert_eq!(left.into_inner(), 123);
let right: Either<u32, _> = Right(123);
assert_eq!(right.into_inner(), 123);
sourcepub fn map<F, M>(self, f: F) -> Either<M, M>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(T) -> M,
pub fn map<F, M>(self, f: F) -> Either<M, M>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
where
F: FnOnce(T) -> M,
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
Map f
over the contained value and return the result in the
corresponding variant.
use either::*;
let value: Either<_, i32> = Right(42);
let other = value.map(|x| x * 2);
assert_eq!(other, Right(84));
Trait Implementations
sourceimpl<L, R, Target> AsMut<[Target]> for Either<L, R> where
L: AsMut<[Target]>,
R: AsMut<[Target]>,
impl<L, R, Target> AsMut<[Target]> for Either<L, R> where
L: AsMut<[Target]>,
R: AsMut<[Target]>,
sourcefn as_mut(&mut self) -> &mut [Target]
fn as_mut(&mut self) -> &mut [Target]
Performs the conversion.
sourceimpl<L, R, Target> AsRef<[Target]> for Either<L, R> where
L: AsRef<[Target]>,
R: AsRef<[Target]>,
impl<L, R, Target> AsRef<[Target]> for Either<L, R> where
L: AsRef<[Target]>,
R: AsRef<[Target]>,
sourceimpl<L: Clone, R: Clone> Clone for Either<L, R>
impl<L: Clone, R: Clone> Clone for Either<L, R>
sourcefn clone(&self) -> Either<L, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
fn clone(&self) -> Either<L, R>ⓘNotable traits for Either<L, R>impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
L: Iterator,
R: Iterator<Item = L::Item>, type Item = L::Item;
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl<L, R> DoubleEndedIterator for Either<L, R> where
L: DoubleEndedIterator,
R: DoubleEndedIterator<Item = L::Item>,
impl<L, R> DoubleEndedIterator for Either<L, R> where
L: DoubleEndedIterator,
R: DoubleEndedIterator<Item = L::Item>,
sourcefn next_back(&mut self) -> Option<Self::Item>
fn next_back(&mut self) -> Option<Self::Item>
Removes and returns an element from the end of the iterator. Read more
sourcefn advance_back_by(&mut self, n: usize) -> Result<(), usize>
fn advance_back_by(&mut self, n: usize) -> Result<(), usize>
iter_advance_by
)Advances the iterator from the back by n
elements. Read more
1.37.0 · sourcefn nth_back(&mut self, n: usize) -> Option<Self::Item>
fn nth_back(&mut self, n: usize) -> Option<Self::Item>
Returns the n
th element from the end of the iterator. Read more
1.27.0 · sourcefn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R where
F: FnMut(B, Self::Item) -> R,
R: Try<Output = B>,
fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R where
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
sourceimpl<L, R> ExactSizeIterator for Either<L, R> where
L: ExactSizeIterator,
R: ExactSizeIterator<Item = L::Item>,
impl<L, R> ExactSizeIterator for Either<L, R> where
L: ExactSizeIterator,
R: ExactSizeIterator<Item = L::Item>,
sourceimpl<L, R, A> Extend<A> for Either<L, R> where
L: Extend<A>,
R: Extend<A>,
impl<L, R, A> Extend<A> for Either<L, R> where
L: Extend<A>,
R: Extend<A>,
sourcefn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = A>,
fn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = A>,
Extends a collection with the contents of an iterator. Read more
sourcefn extend_one(&mut self, item: A)
fn extend_one(&mut self, item: A)
extend_one
)Extends a collection with exactly one element.
sourcefn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)Reserves capacity in a collection for the given number of additional elements. Read more
sourceimpl<L, R> From<Result<R, L>> for Either<L, R>
impl<L, R> From<Result<R, L>> for Either<L, R>
Convert from Result
to Either
with Ok => Right
and Err => Left
.
sourceimpl<L, R> Into<Result<R, L>> for Either<L, R>
impl<L, R> Into<Result<R, L>> for Either<L, R>
Convert from Either
to Result
with Right => Ok
and Left => Err
.
sourceimpl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>,
impl<L, R> Iterator for Either<L, R> where
L: Iterator,
R: Iterator<Item = L::Item>,
Either<L, R>
is an iterator if both L
and R
are iterators.
sourcefn next(&mut self) -> Option<Self::Item>
fn next(&mut self) -> Option<Self::Item>
Advances the iterator and returns the next value. Read more
sourcefn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
Returns the bounds on the remaining length of the iterator. Read more
sourcefn fold<Acc, G>(self, init: Acc, f: G) -> Acc where
G: FnMut(Acc, Self::Item) -> Acc,
fn fold<Acc, G>(self, init: Acc, f: G) -> Acc where
G: FnMut(Acc, Self::Item) -> Acc,
Folds every element into an accumulator by applying an operation, returning the final result. Read more
sourcefn count(self) -> usize
fn count(self) -> usize
Consumes the iterator, counting the number of iterations and returning it. Read more
sourcefn last(self) -> Option<Self::Item>
fn last(self) -> Option<Self::Item>
Consumes the iterator, returning the last element. Read more
sourcefn nth(&mut self, n: usize) -> Option<Self::Item>
fn nth(&mut self, n: usize) -> Option<Self::Item>
Returns the n
th element of the iterator. Read more
sourcefn collect<B>(self) -> B where
B: FromIterator<Self::Item>,
fn collect<B>(self) -> B where
B: FromIterator<Self::Item>,
Transforms an iterator into a collection. Read more
sourcefn all<F>(&mut self, f: F) -> bool where
F: FnMut(Self::Item) -> bool,
fn all<F>(&mut self, f: F) -> bool where
F: FnMut(Self::Item) -> bool,
Tests if every element of the iterator matches a predicate. Read more
sourcefn advance_by(&mut self, n: usize) -> Result<(), usize>
fn advance_by(&mut self, n: usize) -> Result<(), usize>
iter_advance_by
)Advances the iterator by n
elements. Read more
1.28.0 · sourcefn step_by(self, step: usize) -> StepBy<Self>
fn step_by(self, step: usize) -> StepBy<Self>
Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more
1.0.0 · sourcefn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> where
U: IntoIterator<Item = Self::Item>,
fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter> where
U: IntoIterator<Item = Self::Item>,
Takes two iterators and creates a new iterator over both in sequence. Read more
1.0.0 · sourcefn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> where
U: IntoIterator,
fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter> where
U: IntoIterator,
‘Zips up’ two iterators into a single iterator of pairs. Read more
sourcefn intersperse(self, separator: Self::Item) -> Intersperse<Self> where
Self::Item: Clone,
fn intersperse(self, separator: Self::Item) -> Intersperse<Self> where
Self::Item: Clone,
iter_intersperse
)Creates a new iterator which places a copy of separator
between adjacent
items of the original iterator. Read more
sourcefn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> where
G: FnMut() -> Self::Item,
fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> where
G: FnMut() -> Self::Item,
iter_intersperse
)Creates a new iterator which places an item generated by separator
between adjacent items of the original iterator. Read more
1.0.0 · sourcefn map<B, F>(self, f: F) -> Map<Self, F> where
F: FnMut(Self::Item) -> B,
fn map<B, F>(self, f: F) -> Map<Self, F> where
F: FnMut(Self::Item) -> B,
Takes a closure and creates an iterator which calls that closure on each element. Read more
1.21.0 · sourcefn for_each<F>(self, f: F) where
F: FnMut(Self::Item),
fn for_each<F>(self, f: F) where
F: FnMut(Self::Item),
Calls a closure on each element of an iterator. Read more
1.0.0 · sourcefn filter<P>(self, predicate: P) -> Filter<Self, P> where
P: FnMut(&Self::Item) -> bool,
fn filter<P>(self, predicate: P) -> Filter<Self, P> where
P: FnMut(&Self::Item) -> bool,
Creates an iterator which uses a closure to determine if an element should be yielded. Read more
1.0.0 · sourcefn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
F: FnMut(Self::Item) -> Option<B>,
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
F: FnMut(Self::Item) -> Option<B>,
Creates an iterator that both filters and maps. Read more
1.0.0 · sourcefn enumerate(self) -> Enumerate<Self>
fn enumerate(self) -> Enumerate<Self>
Creates an iterator which gives the current iteration count as well as the next value. Read more
1.0.0 · sourcefn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
P: FnMut(&Self::Item) -> bool,
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
P: FnMut(&Self::Item) -> bool,
1.0.0 · sourcefn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
P: FnMut(&Self::Item) -> bool,
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
P: FnMut(&Self::Item) -> bool,
Creates an iterator that yields elements based on a predicate. Read more
1.57.0 · sourcefn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> where
P: FnMut(Self::Item) -> Option<B>,
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> where
P: FnMut(Self::Item) -> Option<B>,
Creates an iterator that both yields elements based on a predicate and maps. Read more
1.0.0 · sourcefn skip(self, n: usize) -> Skip<Self>
fn skip(self, n: usize) -> Skip<Self>
Creates an iterator that skips the first n
elements. Read more
1.0.0 · sourcefn take(self, n: usize) -> Take<Self>
fn take(self, n: usize) -> Take<Self>
Creates an iterator that yields the first n
elements, or fewer
if the underlying iterator ends sooner. Read more
1.0.0 · sourcefn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
F: FnMut(&mut St, Self::Item) -> Option<B>,
fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
F: FnMut(&mut St, Self::Item) -> Option<B>,
1.0.0 · sourcefn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
U: IntoIterator,
F: FnMut(Self::Item) -> U,
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
U: IntoIterator,
F: FnMut(Self::Item) -> U,
Creates an iterator that works like map, but flattens nested structure. Read more
1.29.0 · sourcefn flatten(self) -> Flatten<Self> where
Self::Item: IntoIterator,
fn flatten(self) -> Flatten<Self> where
Self::Item: IntoIterator,
Creates an iterator that flattens nested structure. Read more
1.0.0 · sourcefn inspect<F>(self, f: F) -> Inspect<Self, F> where
F: FnMut(&Self::Item),
fn inspect<F>(self, f: F) -> Inspect<Self, F> where
F: FnMut(&Self::Item),
Does something with each element of an iterator, passing the value on. Read more
1.0.0 · sourcefn by_ref(&mut self) -> &mut Self
fn by_ref(&mut self) -> &mut Self
Borrows an iterator, rather than consuming it. Read more
sourcefn try_collect<B>(
&mut self
) -> <<Self::Item as Try>::Residual as Residual<B>>::TryType where
B: FromIterator<<Self::Item as Try>::Output>,
Self::Item: Try,
<Self::Item as Try>::Residual: Residual<B>,
fn try_collect<B>(
&mut self
) -> <<Self::Item as Try>::Residual as Residual<B>>::TryType where
B: FromIterator<<Self::Item as Try>::Output>,
Self::Item: Try,
<Self::Item as Try>::Residual: Residual<B>,
iterator_try_collect
)Fallibly transforms an iterator into a collection, short circuiting if a failure is encountered. Read more
sourcefn collect_into<E>(self, collection: &mut E) -> &mut E where
E: Extend<Self::Item>,
fn collect_into<E>(self, collection: &mut E) -> &mut E where
E: Extend<Self::Item>,
iter_collect_into
)Collects all the items from an iterator into a collection. Read more
1.0.0 · sourcefn partition<B, F>(self, f: F) -> (B, B) where
B: Default + Extend<Self::Item>,
F: FnMut(&Self::Item) -> bool,
fn partition<B, F>(self, f: F) -> (B, B) where
B: Default + Extend<Self::Item>,
F: FnMut(&Self::Item) -> bool,
Consumes an iterator, creating two collections from it. Read more
sourcefn partition_in_place<'a, T, P>(self, predicate: P) -> usize where
T: 'a,
Self: DoubleEndedIterator<Item = &'a mut T>,
P: FnMut(&T) -> bool,
fn partition_in_place<'a, T, P>(self, predicate: P) -> usize where
T: 'a,
Self: DoubleEndedIterator<Item = &'a mut T>,
P: FnMut(&T) -> bool,
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
sourcefn is_partitioned<P>(self, predicate: P) -> bool where
P: FnMut(Self::Item) -> bool,
fn is_partitioned<P>(self, predicate: P) -> bool where
P: FnMut(Self::Item) -> bool,
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 · sourcefn try_fold<B, F, R>(&mut self, init: B, f: F) -> R where
F: FnMut(B, Self::Item) -> R,
R: Try<Output = B>,
fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R where
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 · sourcefn try_for_each<F, R>(&mut self, f: F) -> R where
F: FnMut(Self::Item) -> R,
R: Try<Output = ()>,
fn try_for_each<F, R>(&mut self, f: F) -> R where
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 · sourcefn reduce<F>(self, f: F) -> Option<Self::Item> where
F: FnMut(Self::Item, Self::Item) -> Self::Item,
fn reduce<F>(self, f: F) -> Option<Self::Item> where
F: FnMut(Self::Item, Self::Item) -> Self::Item,
Reduces the elements to a single one, by repeatedly applying a reducing operation. Read more
sourcefn try_reduce<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType where
F: FnMut(Self::Item, Self::Item) -> R,
R: Try<Output = Self::Item>,
<R as Try>::Residual: Residual<Option<Self::Item>>,
fn try_reduce<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType where
F: FnMut(Self::Item, Self::Item) -> R,
R: Try<Output = Self::Item>,
<R as Try>::Residual: Residual<Option<Self::Item>>,
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
1.0.0 · sourcefn any<F>(&mut self, f: F) -> bool where
F: FnMut(Self::Item) -> bool,
fn any<F>(&mut self, f: F) -> bool where
F: FnMut(Self::Item) -> bool,
Tests if any element of the iterator matches a predicate. Read more
1.0.0 · sourcefn find<P>(&mut self, predicate: P) -> Option<Self::Item> where
P: FnMut(&Self::Item) -> bool,
fn find<P>(&mut self, predicate: P) -> Option<Self::Item> where
P: FnMut(&Self::Item) -> bool,
Searches for an element of an iterator that satisfies a predicate. Read more
1.30.0 · sourcefn find_map<B, F>(&mut self, f: F) -> Option<B> where
F: FnMut(Self::Item) -> Option<B>,
fn find_map<B, F>(&mut self, f: F) -> Option<B> where
F: FnMut(Self::Item) -> Option<B>,
Applies function to the elements of iterator and returns the first non-none result. Read more
sourcefn try_find<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType where
F: FnMut(&Self::Item) -> R,
R: Try<Output = bool>,
<R as Try>::Residual: Residual<Option<Self::Item>>,
fn try_find<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType where
F: FnMut(&Self::Item) -> R,
R: Try<Output = bool>,
<R as Try>::Residual: Residual<Option<Self::Item>>,
try_find
)Applies function to the elements of iterator and returns the first true result or the first error. Read more
1.0.0 · sourcefn position<P>(&mut self, predicate: P) -> Option<usize> where
P: FnMut(Self::Item) -> bool,
fn position<P>(&mut self, predicate: P) -> Option<usize> where
P: FnMut(Self::Item) -> bool,
Searches for an element in an iterator, returning its index. Read more
1.0.0 · sourcefn rposition<P>(&mut self, predicate: P) -> Option<usize> where
P: FnMut(Self::Item) -> bool,
Self: ExactSizeIterator + DoubleEndedIterator,
fn rposition<P>(&mut self, predicate: P) -> Option<usize> where
P: FnMut(Self::Item) -> bool,
Self: ExactSizeIterator + DoubleEndedIterator,
Searches for an element in an iterator from the right, returning its index. Read more
1.0.0 · sourcefn max(self) -> Option<Self::Item> where
Self::Item: Ord,
fn max(self) -> Option<Self::Item> where
Self::Item: Ord,
Returns the maximum element of an iterator. Read more
1.0.0 · sourcefn min(self) -> Option<Self::Item> where
Self::Item: Ord,
fn min(self) -> Option<Self::Item> where
Self::Item: Ord,
Returns the minimum element of an iterator. Read more
1.6.0 · sourcefn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
F: FnMut(&Self::Item) -> B,
fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
F: FnMut(&Self::Item) -> B,
Returns the element that gives the maximum value from the specified function. Read more
1.15.0 · sourcefn max_by<F>(self, compare: F) -> Option<Self::Item> where
F: FnMut(&Self::Item, &Self::Item) -> Ordering,
fn max_by<F>(self, compare: F) -> Option<Self::Item> where
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 · sourcefn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
F: FnMut(&Self::Item) -> B,
fn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where
B: Ord,
F: FnMut(&Self::Item) -> B,
Returns the element that gives the minimum value from the specified function. Read more
1.15.0 · sourcefn min_by<F>(self, compare: F) -> Option<Self::Item> where
F: FnMut(&Self::Item, &Self::Item) -> Ordering,
fn min_by<F>(self, compare: F) -> Option<Self::Item> where
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 · sourcefn rev(self) -> Rev<Self> where
Self: DoubleEndedIterator,
fn rev(self) -> Rev<Self> where
Self: DoubleEndedIterator,
Reverses an iterator’s direction. Read more
1.0.0 · sourcefn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where
FromA: Default + Extend<A>,
FromB: Default + Extend<B>,
Self: Iterator<Item = (A, B)>,
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where
FromA: Default + Extend<A>,
FromB: Default + Extend<B>,
Self: Iterator<Item = (A, B)>,
Converts an iterator of pairs into a pair of containers. Read more
1.36.0 · sourcefn copied<'a, T>(self) -> Copied<Self> where
T: 'a + Copy,
Self: Iterator<Item = &'a T>,
fn copied<'a, T>(self) -> Copied<Self> where
T: 'a + Copy,
Self: Iterator<Item = &'a T>,
Creates an iterator which copies all of its elements. Read more
1.0.0 · sourcefn cloned<'a, T>(self) -> Cloned<Self> where
T: 'a + Clone,
Self: Iterator<Item = &'a T>,
fn cloned<'a, T>(self) -> Cloned<Self> where
T: 'a + Clone,
Self: Iterator<Item = &'a T>,
1.0.0 · sourcefn cycle(self) -> Cycle<Self> where
Self: Clone,
fn cycle(self) -> Cycle<Self> where
Self: Clone,
Repeats an iterator endlessly. Read more
1.11.0 · sourcefn sum<S>(self) -> S where
S: Sum<Self::Item>,
fn sum<S>(self) -> S where
S: Sum<Self::Item>,
Sums the elements of an iterator. Read more
1.11.0 · sourcefn product<P>(self) -> P where
P: Product<Self::Item>,
fn product<P>(self) -> P where
P: Product<Self::Item>,
Iterates over the entire iterator, multiplying all the elements Read more
1.5.0 · sourcefn cmp<I>(self, other: I) -> Ordering where
I: IntoIterator<Item = Self::Item>,
Self::Item: Ord,
fn cmp<I>(self, other: I) -> Ordering where
I: IntoIterator<Item = Self::Item>,
Self::Item: Ord,
Lexicographically compares the elements of this Iterator
with those
of another. Read more
sourcefn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,
fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,
iter_order_by
)Lexicographically compares the elements of this Iterator
with those
of another with respect to the specified comparison function. Read more
1.5.0 · sourcefn partial_cmp<I>(self, other: I) -> Option<Ordering> where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
fn partial_cmp<I>(self, other: I) -> Option<Ordering> where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
Lexicographically compares the elements of this Iterator
with those
of another. Read more
sourcefn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering> where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering> where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
iter_order_by
)Lexicographically compares the elements of this Iterator
with those
of another with respect to the specified comparison function. Read more
1.5.0 · sourcefn eq<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialEq<<I as IntoIterator>::Item>,
fn eq<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialEq<<I as IntoIterator>::Item>,
sourcefn eq_by<I, F>(self, other: I, eq: F) -> bool where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,
fn eq_by<I, F>(self, other: I, eq: F) -> bool where
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,
iter_order_by
)1.5.0 · sourcefn ne<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialEq<<I as IntoIterator>::Item>,
fn ne<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialEq<<I as IntoIterator>::Item>,
1.5.0 · sourcefn lt<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
fn lt<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
Determines if the elements of this Iterator
are lexicographically
less than those of another. Read more
1.5.0 · sourcefn le<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
fn le<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
Determines if the elements of this Iterator
are lexicographically
less or equal to those of another. Read more
1.5.0 · sourcefn gt<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
fn gt<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
Determines if the elements of this Iterator
are lexicographically
greater than those of another. Read more
1.5.0 · sourcefn ge<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
fn ge<I>(self, other: I) -> bool where
I: IntoIterator,
Self::Item: PartialOrd<<I as IntoIterator>::Item>,
Determines if the elements of this Iterator
are lexicographically
greater than or equal to those of another. Read more
sourcefn is_sorted(self) -> bool where
Self::Item: PartialOrd<Self::Item>,
fn is_sorted(self) -> bool where
Self::Item: PartialOrd<Self::Item>,
is_sorted
)Checks if the elements of this iterator are sorted. Read more
sourcefn is_sorted_by<F>(self, compare: F) -> bool where
F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>,
fn is_sorted_by<F>(self, compare: F) -> bool where
F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>,
is_sorted
)Checks if the elements of this iterator are sorted using the given comparator function. Read more
sourcefn is_sorted_by_key<F, K>(self, f: F) -> bool where
F: FnMut(Self::Item) -> K,
K: PartialOrd<K>,
fn is_sorted_by_key<F, K>(self, f: F) -> bool where
F: FnMut(Self::Item) -> K,
K: PartialOrd<K>,
is_sorted
)Checks if the elements of this iterator are sorted using the given key extraction function. Read more
sourceimpl<L: Ord, R: Ord> Ord for Either<L, R>
impl<L: Ord, R: Ord> Ord for Either<L, R>
sourceimpl<L: PartialOrd, R: PartialOrd> PartialOrd<Either<L, R>> for Either<L, R>
impl<L: PartialOrd, R: PartialOrd> PartialOrd<Either<L, R>> for Either<L, R>
sourcefn partial_cmp(&self, other: &Either<L, R>) -> Option<Ordering>
fn partial_cmp(&self, other: &Either<L, R>) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
impl<L: Copy, R: Copy> Copy for Either<L, R>
impl<L: Eq, R: Eq> Eq for Either<L, R>
impl<L, R> StructuralEq for Either<L, R>
impl<L, R> StructuralPartialEq for Either<L, R>
Auto Trait Implementations
impl<L, R> RefUnwindSafe for Either<L, R> where
L: RefUnwindSafe,
R: RefUnwindSafe,
impl<L, R> Send for Either<L, R> where
L: Send,
R: Send,
impl<L, R> Sync for Either<L, R> where
L: Sync,
R: Sync,
impl<L, R> Unpin for Either<L, R> where
L: Unpin,
R: Unpin,
impl<L, R> UnwindSafe for Either<L, R> where
L: UnwindSafe,
R: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more