Enum either::Either

pub enum Either<L, R> {
    Left(L),
    Right(R),
}

Either represents an alternative holding one value out of either of the two possible values.

Either is a general purpose sum type of two parts. For representing success or error, use the regular Result<T, E> instead.

Variants

Left(L)

A value of type L.

Right(R)

A value of type R.

Methods

impl<L, R> Either<L, R>

fn is_left(&self) -> bool

fn is_right(&self) -> bool

fn left(self) -> Option<L>

fn right(self) -> Option<R>

fn as_ref(&self) -> Either<&L, &R>

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

fn flip(self) -> Either<R, L>

Trait Implementations

impl<L: Debug, R: Debug> Debug for Either<L, R>

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

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

fn hash<__HLR: Hasher>(&self, __arg_0: &mut __HLR)

Feeds this value into the state given, updating the hasher as necessary.

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

Feeds a slice of this type into the state provided.

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

fn cmp(&self, __arg_0: &Either<L, R>) -> Ordering

This method returns an Ordering between self and other.

impl<L: PartialOrd, R: PartialOrd> PartialOrd for Either<L, R>

fn partial_cmp(&self, __arg_0: &Either<L, R>) -> Option<Ordering>

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

fn lt(&self, __arg_0: &Either<L, R>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, __arg_0: &Either<L, R>) -> bool

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

fn gt(&self, __arg_0: &Either<L, R>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, __arg_0: &Either<L, R>) -> bool

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

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

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

fn eq(&self, __arg_0: &Either<L, R>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &Either<L, R>) -> bool

This method tests for !=.

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

fn clone(&self) -> Either<L, R>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<L: Copy, R: Copy> Copy 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.

fn from(r: Result<R, L>) -> Self

Performs the conversion.

impl<L, R> Into<Result<R, L>> for Either<L, R>

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

fn into(self) -> Result<R, L>

Performs the conversion.

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.

type Item = L::Item

The type of the elements being iterated over.

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

Advances the iterator and returns the next value.

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

Returns the bounds on the remaining length of the iterator.

fn count(self) -> usize

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

fn last(self) -> Option<Self::Item>

Consumes the iterator, returning the last element.

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

Consumes the n first elements of the iterator, then returns the next() one.

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

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

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

'Zips up' two iterators into a single iterator of pairs.

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.

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.

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.

fn enumerate(self) -> Enumerate<Self>

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

fn peekable(self) -> Peekable<Self>

Creates an iterator which can use peek to look at the next element of the iterator without consuming it.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where P: FnMut(&Self::Item) -> bool

Creates an iterator that [skip()]s elements based on a predicate.

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.

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

Creates an iterator that skips the first n elements.

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

Creates an iterator that yields its first n elements.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where F: FnMut(&mut St, Self::Item) -> Option<B>

An iterator adaptor similar to [fold()] that holds internal state and produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where F: FnMut(Self::Item) -> U, U: IntoIterator

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

fn fuse(self) -> Fuse<Self>

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F> where F: FnMut(&Self::Item) -> ()

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

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

Borrows an iterator, rather than consuming it.

fn collect<B>(self) -> B where B: FromIterator<Self::Item>

Transforms an iterator into a collection.

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.

fn fold<B, F>(self, init: B, f: F) -> B where F: FnMut(B, Self::Item) -> B

An iterator adaptor that applies a function, producing a single, final value.

fn all<F>(&mut self, f: F) -> bool where F: FnMut(Self::Item) -> bool

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool where F: FnMut(Self::Item) -> bool

Tests if any element of the iterator matches a predicate.

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

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

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.

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.

fn max(self) -> Option<Self::Item> where Self::Item: Ord

Returns the maximum element of an iterator.

fn min(self) -> Option<Self::Item> where Self::Item: Ord

Returns the minimum element of an iterator.

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.

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.

fn rev(self) -> Rev<Self> where Self: DoubleEndedIterator

Reverses an iterator's direction.

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.

fn cloned<'a, T>(self) -> Cloned<Self> where Self: Iterator<Item=&'a T>, T: 'a + Clone

Creates an iterator which clone()s all of its elements.

fn cycle(self) -> Cycle<Self> where Self: Clone

Repeats an iterator endlessly.

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

Sums the elements of an iterator.

fn product<P>(self) -> P where P: Product<Self::Item>

Iterates over the entire iterator, multiplying all the elements

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.

fn partial_cmp<I>(self, other: I) -> Option<Ordering> where I: IntoIterator, Self::Item: PartialOrd<I::Item>

Lexicographically compares the elements of this Iterator with those of another.

fn eq<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>

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

fn ne<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>

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

fn lt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>

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

fn le<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>

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

fn gt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>

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

fn ge<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>

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

impl<L, R> DoubleEndedIterator for Either<L, R> where L: DoubleEndedIterator, R: DoubleEndedIterator<Item=L::Item>

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

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

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

fn len(&self) -> usize

Returns the exact number of times the iterator will iterate.

fn is_empty(&self) -> bool

Unstable (exact_size_is_empty)

Returns whether the iterator is empty.

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

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

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

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

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

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

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

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

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

Read the exact number of bytes required to fill buf.

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

Creates a "by reference" adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an Iterator over its bytes.

fn chars(self) -> Chars<Self>

Unstable (io)

: the semantics of a partial read/write of where errors happen is currently unclear and may change

Transforms this Read instance to an Iterator over chars.

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

Creates an adaptor which will chain this stream with another.

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

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

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

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

Fills the internal buffer of this object, returning the buffer contents.

fn consume(&mut self, amt: usize)

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

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

Read all bytes into buf until the delimiter byte is reached.

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

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

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

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

fn lines(self) -> Lines<Self>

Returns an iterator over the lines of this reader.

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

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

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

Write a buffer into this object, returning how many bytes were written.

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

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

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

Attempts to write an entire buffer into this write.

fn write_fmt(&mut self, fmt: Arguments) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

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

Creates a "by reference" adaptor for this instance of Write.

impl<L, R, Target> AsRef<Target> for Either<L, R> where L: AsRef<Target>, R: AsRef<Target>

fn as_ref(&self) -> &Target

Performs the conversion.

impl<L, R, Target> AsMut<Target> for Either<L, R> where L: AsMut<Target>, R: AsMut<Target>

fn as_mut(&mut self) -> &mut Target

Performs the conversion.

impl<L, R> Deref for Either<L, R> where L: Deref, R: Deref<Target=L::Target>

type Target = L::Target

The resulting type after dereferencing

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

The method called to dereference a value

impl<L, R> DerefMut for Either<L, R> where L: DerefMut, R: DerefMut<Target=L::Target>

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

The method called to mutably dereference a value