Enum arrow2::Either

source · [−]
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

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);

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);

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);

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));

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"));

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));

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

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

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"));

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));

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));

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);

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]);

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));

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));

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]));

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");

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());

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");

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");

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);

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);

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();

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();

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");

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");

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);

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())));

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())));

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())));

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);

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);

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);

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

Converts this type into a mutable reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a mutable reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a mutable reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a mutable reference of the (usually inferred) input type.

Converts this type into a mutable reference of the (usually inferred) input type.

Converts this type into a mutable reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a shared reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a shared reference of the (usually inferred) input type.

Requires crate feature use_std.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Requires crate feature "use_std"

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

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

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

Read all bytes until a newline (the 0xA byte) is reached, and append them to the provided buffer. You do not need to clear the buffer before appending. Read more

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

Check if the underlying Read has any data left to be read. Read more

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

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

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

The resulting type after dereferencing.

Dereferences the value.

Mutably dereferences the value.

Formats the value using the given formatter. Read more

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

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

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

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

Advances the iterator from the back by n elements. Read more

Returns the nth element from the end of the iterator. Read more

This is the reverse version of Iterator::try_fold(): it takes elements starting from the back of the iterator. Read more

Either implements Error if both L and R implement it.

The lower-level source of this error, if any. Read more

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

Read more
👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

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

Provides type based access to context intended for error reports. Read more

Returns the exact remaining length of the iterator. Read more

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

Returns true if the iterator is empty. Read more

Extends a collection with the contents of an iterator. Read more

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

Extends a collection with exactly one element.

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

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

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

Converts to this type from the input type.

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

The type of value produced on completion.

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

Feeds this value into the given Hasher. Read more

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

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

Converts this type into the (usually inferred) input type.

Either<L, R> is an iterator if both L and R are iterators.

The type of the elements being iterated over.

Advances the iterator and returns the next value. Read more

Returns the bounds on the remaining length of the iterator. Read more

Folds every element into an accumulator by applying an operation, returning the final result. Read more

Calls a closure on each element of an iterator. Read more

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

Consumes the iterator, returning the last element. Read more

Returns the nth element of the iterator. Read more

Transforms an iterator into a collection. Read more

Consumes an iterator, creating two collections from it. Read more

Tests if every element of the iterator matches a predicate. Read more

Tests if any element of the iterator matches a predicate. Read more

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

Applies function to the elements of iterator and returns the first non-none result. Read more

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

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

Advances the iterator by n elements. Read more

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more

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

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

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

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator. Read more

Takes a closure and creates an iterator which calls that closure on each element. Read more

Creates an iterator which uses a closure to determine if an element should be yielded. Read more

Creates an iterator that both filters and maps. Read more

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

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information. Read more

Creates an iterator that skips elements based on a predicate. Read more

Creates an iterator that yields elements based on a predicate. Read more

Creates an iterator that both yields elements based on a predicate and maps. Read more

Creates an iterator that skips the first n elements. Read more

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner. Read more

An iterator adapter similar to fold that holds internal state and produces a new iterator. Read more

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

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

Does something with each element of an iterator, passing the value on. Read more

Borrows an iterator, rather than consuming it. Read more

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

Collects all the items from an iterator into a collection. Read more

🔬 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

An iterator method that applies a function as long as it returns successfully, producing a single, final value. Read more

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

Reduces the elements to a single one, by repeatedly applying a reducing operation. Read more

🔬 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

🔬 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

Returns the element that gives the maximum value from the specified function. Read more

Returns the element that gives the maximum value with respect to the specified comparison function. Read more

Returns the element that gives the minimum value from the specified function. Read more

Returns the element that gives the minimum value with respect to the specified comparison function. Read more

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

Creates an iterator which copies all of its elements. Read more

Creates an iterator which clones all of its elements. Read more

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

Returns an iterator over N elements of the iterator at a time. Read more

Sums the elements of an iterator. Read more

Iterates over the entire iterator, multiplying all the elements Read more

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

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

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

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

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

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function. Read more

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

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

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

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

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

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

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

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

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

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

Compares and returns the maximum of two values. Read more

Compares and returns the minimum of two values. Read more

Restrict a value to a certain interval. Read more

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more

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

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

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

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

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

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

Requires crate feature "use_std"

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

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

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

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

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

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

Determines if this Reader has an efficient read_vectored implementation. Read more

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

Pull some bytes from this source into the specified buffer. Read more

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

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

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

Transforms this Read instance to an Iterator over its bytes. Read more

Creates an adapter which will chain this stream with another. Read more

Creates an adapter which will read at most limit bytes from it. Read more

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

Requires crate feature "use_std"

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

Rewind to the beginning of a stream. Read more

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

Returns the length of this stream (in bytes). Read more

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

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

Requires crate feature "use_std"

Write a buffer into this writer, returning how many bytes were written. Read more

Attempts to write an entire buffer into this writer. Read more

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

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

Like write, except that it writes from a slice of buffers. Read more

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

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

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

Attempts to write multiple buffers into this writer. Read more

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

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Convert self to an [UncasedStr].

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns an iterator over the lines of this reader, where each line is represented as a byte string. Read more

Returns an iterator over byte-terminated records of this reader, where each record is represented as a byte string. Read more

Executes the given closure on each line in the underlying reader. Read more

Executes the given closure on each byte-terminated record in the underlying reader. Read more

Executes the given closure on each line in the underlying reader. Read more

Executes the given closure on each byte-terminated record in the underlying reader. Read more

source

fn __clone_box(&self, Private) -> *mut ()

Compare self to key and return true if they are equal.

Returns the argument unchanged.

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

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

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

Wrap this future in an Either future, making it the left-hand variant of that Either. Read more

Wrap this future in an Either future, making it the right-hand variant of that Either. Read more

Convert this future into a single element stream. Read more

Flatten the execution of this future when the output of this future is itself another future. Read more

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

Fuse a future such that poll will never again be called once it has completed. This method can be used to turn any Future into a FusedFuture. Read more

Do something with the output of a future before passing it on. Read more

Catches unwinding panics while polling the future. Read more

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

Turn this future into a future that yields () on completion and sends its output to another future on a separate task. Read more

Wrap the future in a Box, pinning it. Read more

Wrap the future in a Box, pinning it. Read more

Turns a Future<Output = T> into a TryFuture<Ok = T, Error = ()>. Read more

Turns a Future<Output = T> into a TryFuture<Ok = T, Error = Never>. Read more

A convenience for calling Future::poll on Unpin future types.

Evaluates and consumes the future, returning the resulting output if the future is ready after the first call to Future::poll. Read more

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The output that the future will produce on completion.

Which kind of future are we turning this into?

Creates a future from a value. Read more

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

Alternate elements from two iterators until both have run out. Read more

Alternate elements from two iterators until at least one of them has run out. Read more

An iterator adaptor to insert a particular value between each element of the adapted iterator. Read more

An iterator adaptor to insert a particular value created by a function between each element of the adapted iterator. Read more

Create an iterator which iterates over both this and the specified iterator simultaneously, yielding pairs of two optional elements. Read more

Create an iterator which iterates over both this and the specified iterator simultaneously, yielding pairs of elements. Read more

A “meta iterator adaptor”. Its closure receives a reference to the iterator and may pick off as many elements as it likes, to produce the next iterator element. Read more

Return an iterable that can group iterator elements. Consecutive elements that map to the same key (“runs”), are assigned to the same group. Read more

Return an iterable that can chunk the iterator. Read more

Return an iterator over all contiguous windows producing tuples of a specific size (up to 12). Read more

Return an iterator over all windows, wrapping back to the first elements when the window would otherwise exceed the length of the iterator, producing tuples of a specific size (up to 12). Read more

Return an iterator that groups the items in tuples of a specific size (up to 12). Read more

Split into an iterator pair that both yield all elements from the original iterator. Read more

👎 Deprecated since 0.8.0:

Use std .step_by() instead

Return an iterator adaptor that steps n elements in the base iterator for each iteration. Read more

Convert each item of the iterator using the Into trait. Read more

👎 Deprecated since 0.10.0:

Use .map_ok() instead

See .map_ok().

Return an iterator adaptor that applies the provided closure to every Result::Ok value. Result::Err values are unchanged. Read more

Return an iterator adaptor that filters every Result::Ok value with the provided closure. Result::Err values are unchanged. Read more

Return an iterator adaptor that filters and transforms every Result::Ok value with the provided closure. Result::Err values are unchanged. Read more

Return an iterator adaptor that flattens every Result::Ok value into a series of Result::Ok values. Result::Err values are unchanged. Read more

Return an iterator adaptor that merges the two base iterators in ascending order. If both base iterators are sorted (ascending), the result is sorted. Read more

Return an iterator adaptor that merges the two base iterators in order. This is much like .merge() but allows for a custom ordering. Read more

Create an iterator that merges items from both this and the specified iterator in ascending order. Read more

Return an iterator adaptor that flattens an iterator of iterators by merging them in ascending order. Read more

Return an iterator adaptor that flattens an iterator of iterators by merging them according to the given closure. Read more

Return an iterator adaptor that iterates over the cartesian product of the element sets of two iterators self and J. Read more

Return an iterator adaptor that iterates over the cartesian product of all subiterators returned by meta-iterator self. Read more

Return an iterator adaptor that uses the passed-in closure to optionally merge together consecutive elements. Read more

Remove duplicates from sections of consecutive identical elements. If the iterator is sorted, all elements will be unique. Read more

Remove duplicates from sections of consecutive identical elements, determining equality using a comparison function. If the iterator is sorted, all elements will be unique. Read more

Remove duplicates from sections of consecutive identical elements, while keeping a count of how many repeated elements were present. If the iterator is sorted, all elements will be unique. Read more

Remove duplicates from sections of consecutive identical elements, while keeping a count of how many repeated elements were present. This will determine equality using a comparison function. If the iterator is sorted, all elements will be unique. Read more

Return an iterator adaptor that produces elements that appear more than once during the iteration. Duplicates are detected using hash and equality. Read more

Return an iterator adaptor that produces elements that appear more than once during the iteration. Duplicates are detected using hash and equality. Read more

Return an iterator adaptor that filters out elements that have already been produced once during the iteration. Duplicates are detected using hash and equality. Read more

Return an iterator adaptor that filters out elements that have already been produced once during the iteration. Read more

Return an iterator adaptor that borrows from this iterator and takes items while the closure accept returns true. Read more

Return an iterator adaptor that borrows from a Clone-able iterator to only pick off elements while the predicate accept returns true. Read more

Return an iterator adaptor that filters Option<A> iterator elements and produces A. Stops on the first None encountered. Read more

Return an iterator adaptor that iterates over the combinations of the elements from an iterator. Read more

Return an iterator adaptor that iterates over the k-length combinations of the elements from an iterator. Read more

Return an iterator that iterates over the k-length combinations of the elements from an iterator, with replacement. Read more

Return an iterator adaptor that iterates over all k-permutations of the elements from an iterator. Read more

Return an iterator that iterates through the powerset of the elements from an iterator. Read more

Return an iterator adaptor that pads the sequence to a minimum length of min by filling missing elements using a closure f. Read more

Return an iterator adaptor that wraps each element in a Position to ease special-case handling of the first or last elements. Read more

Return an iterator adaptor that yields the indices of all elements satisfying a predicate, counted from the start of the iterator. Read more

Return an iterator adaptor that applies a mutating function to each element before yielding it. Read more

Advances the iterator and returns the next items grouped in a tuple of a specific size (up to 12). Read more

Collects all items from the iterator into a tuple of a specific size (up to 12). Read more

Find the position and value of the first element satisfying a predicate. Read more

Find the value of the first element satisfying a predicate or return the last element, if any. Read more

Find the value of the first element satisfying a predicate or return the first element, if any. Read more

Returns true if the given item is present in this iterator. Read more

Check whether all elements compare equal. Read more

Check whether all elements are unique (non equal). Read more

Consume the first n elements from the iterator eagerly, and return the same iterator again. Read more

Consume the last n elements from the iterator eagerly, and return the same iterator again. Read more

👎 Deprecated since 0.8.0:

Use .for_each() instead

Run the closure f eagerly on each element of the iterator. Read more

Combine all an iterator’s elements into one element by using Extend. Read more

.collect_vec() is simply a type specialization of Iterator::collect, for convenience. Read more

.try_collect() is more convenient way of writing .collect::<Result<_, _>>() Read more

Assign to each reference in self from the from iterator, stopping at the shortest of the two iterators. Read more

Combine all iterator elements into one String, separated by sep. Read more

Format all iterator elements, separated by sep. Read more

Format all iterator elements, separated by sep. Read more

👎 Deprecated since 0.10.0:

Use .fold_ok() instead

See .fold_ok().

Fold Result values from an iterator. Read more

Fold Option values from an iterator. Read more

👎 Deprecated since 0.10.2:

Use Iterator::reduce instead

Accumulator of the elements in the iterator. Read more

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

An iterator method that applies a function, producing a single, final value. Read more

Iterate over the entire iterator and add all the elements. Read more

Iterate over the entire iterator and multiply all the elements. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. Read more

Sort all iterator elements into a new iterator in ascending order. The key function is called exactly once per key. Read more

Sort the k smallest elements into a new iterator, in ascending order. Read more

Collect all iterator elements into one of two partitions. Unlike Iterator::partition, each partition may have a distinct type. Read more

Partition a sequence of Results into one list of all the Ok elements and another list of all the Err elements. Read more

Return a HashMap of keys mapped to Vecs of values. Keys and values are taken from (Key, Value) tuple pairs yielded by the input iterator. Read more

Return an Iterator on a HashMap. Keys mapped to Vecs of values. The key is specified in the closure. Read more

Constructs a GroupingMap to be used later with one of the efficient group-and-fold operations it allows to perform. Read more

Constructs a GroupingMap to be used later with one of the efficient group-and-fold operations it allows to perform. Read more

Return the minimum and maximum elements in the iterator. Read more

Return the minimum and maximum element of an iterator, as determined by the specified function. Read more

Return the minimum and maximum element of an iterator, as determined by the specified comparison function. Read more

Return the position of the maximum element in the iterator. Read more

Return the position of the maximum element in the iterator, as determined by the specified function. Read more

Return the position of the maximum element in the iterator, as determined by the specified comparison function. Read more

Return the position of the minimum element in the iterator. Read more

Return the position of the minimum element in the iterator, as determined by the specified function. Read more

Return the position of the minimum element in the iterator, as determined by the specified comparison function. Read more

Return the positions of the minimum and maximum elements in the iterator. Read more

Return the postions of the minimum and maximum elements of an iterator, as determined by the specified function. Read more

Return the postions of the minimum and maximum elements of an iterator, as determined by the specified comparison function. Read more

If the iterator yields exactly one element, that element will be returned, otherwise an error will be returned containing an iterator that has the same output as the input iterator. Read more

If the iterator yields no elements, Ok(None) will be returned. If the iterator yields exactly one element, that element will be returned, otherwise an error will be returned containing an iterator that has the same output as the input iterator. Read more

An iterator adaptor that allows the user to peek at multiple .next() values without advancing the base iterator. Read more

Collect the items in this iterator and return a HashMap which contains each item that appears in the iterator and the number of times it appears. Read more

Collect the items in this iterator and return a HashMap which contains each item that appears in the iterator and the number of times it appears, determining identity using a keying function. Read more

Converts an iterator of tuples into a tuple of containers. Read more

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

Unzip this iterator into multiple collections.

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

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

The resulting type after obtaining ownership.

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

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

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type of successful values yielded by this future

The type of failures yielded by this future

Poll this TryFuture as if it were a Future. Read more

Flattens the execution of this future when the successful result of this future is a [Sink]. Read more

Maps this future’s success value to a different value. Read more

Maps this future’s success value to a different value, and permits for error handling resulting in the same type. Read more

Maps this future’s error value to a different value. Read more

Maps this future’s Error to a new error type using the Into trait. Read more

Maps this future’s Ok to a new type using the Into trait. Read more

Executes another future after this one resolves successfully. The success value is passed to a closure to create this subsequent future. Read more

Executes another future if this one resolves to an error. The error value is passed to a closure to create this subsequent future. Read more

Do something with the success value of a future before passing it on. Read more

Do something with the error value of a future before passing it on. Read more

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

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

Unwraps this future’s output, producing a future with this future’s Ok type as its Output type. Read more

Wraps a [TryFuture] into a type that implements Future. Read more

A convenience method for calling [TryFuture::try_poll] on Unpin future types. Read more

The type returned in the event of a conversion error.

Performs the conversion.

Returns either the decoded integer, or an error. Read more