Enum futures::prelude::Never

pub enum Never {}

A type with no possible values.

This is used to indicate values which can never be created, such as the error type of infallible futures.

This type is a stable equivalent to the ! type from std.

Methods

impl Never

pub fn never_into<T>(self) -> T

Convert the Never type into any other type.

Trait Implementations

impl Eq for Never

impl Stream for Never

type Item = Never

Values yielded by the stream.

type Error = Never

Errors yielded by the stream.

fn poll_next(&mut self, &mut Context) -> Result<Async<Option<Never>>, Never>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

impl Debug for Never

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Copy for Never

impl Ord for Never

fn cmp(&self, other: &Never) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

impl Future for Never

type Item = Never

A successful value

type Error = Never

An error

fn poll(&mut self, &mut Context) -> Result<Async<Never>, Never>

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

impl PartialOrd<Never> for Never

fn partial_cmp(&self, other: &Never) -> Option<Ordering>

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

#[must_use] fn lt(&self, other: &Rhs) -> bool

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

#[must_use] fn le(&self, other: &Rhs) -> bool

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

#[must_use] fn gt(&self, other: &Rhs) -> bool

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

#[must_use] fn ge(&self, other: &Rhs) -> bool

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

impl Clone for Never

fn clone(&self) -> Never

Returns a copy of the value.

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

Performs copy-assignment from source.

impl PartialEq<Never> for Never

fn eq(&self, other: &Never) -> bool

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

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.