Enum Either 

pub enum Either<A, B> {
    Left(A),
    Right(B),
}

A value of one of two types.

Either is a Future when both variants are futures with the same output, and a Service when both variants are services with the same request, response, and error types.

Variants

Left(A)

First branch of the type

Right(B)

Second branch of the type

Implementations

impl<A, B> Either<A, B>

pub fn is_left(&self) -> bool

Returns true if the value is the Left variant.

pub fn is_right(&self) -> bool

Returns true if the value is the Right variant.

pub fn left(self) -> Option<A>

Converts the left side of Either<A, B> to an Option<A>.

pub fn right(self) -> Option<B>

Converts the right side of Either<A, B> to an Option<B>.

pub fn as_ref(&self) -> Either<&A, &B>

Converts &Either<A, B> to Either<&A, &B>.

pub fn as_mut(&mut self) -> Either<&mut A, &mut B>

Converts &mut Either<A, B> to Either<&mut A, &mut B>.

impl<T> Either<T, T>

pub fn into_inner(self) -> T

Extracts the value of an Either over two equal types.

Trait Implementations

impl<A, B> Clone for Either<A, B>

where A: Clone, B: Clone,

fn clone(&self) -> Either<A, B>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<A, B> Copy for Either<A, B>

where A: Copy, B: Copy,

impl<A, B> Debug for Either<A, B>

where A: Debug, B: Debug,

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

Formats the value using the given formatter.

impl<A, B> Display for Either<A, B>

where A: Display, B: Display,

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

Formats the value using the given formatter.

impl<A, B> Eq for Either<A, B>

where A: Eq, B: Eq,

impl<A, B> Error for Either<A, B>

where A: Error, B: Error,

Either implements Error if both A and B implement it.

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

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

Provides type-based access to context intended for error reports.

impl From<Either<DecodeError, Error>> for ClientError

fn from(err: Either<DecodeError, Error>) -> Self

Converts to this type from the input type.

impl From<Either<DecodeError, Error>> for WsClientError

fn from(err: Either<DecodeError, Error>) -> Self

Converts to this type from the input type.

impl From<Either<EncodeError, Error>> for ClientError

fn from(err: Either<EncodeError, Error>) -> Self

Converts to this type from the input type.

impl From<Either<EncodeError, Error>> for WsClientError

fn from(err: Either<EncodeError, Error>) -> Self

Converts to this type from the input type.

impl From<Either<PayloadError, Error>> for PayloadError

fn from(err: Either<PayloadError, Error>) -> Self

Converts to this type from the input type.

impl<A, B> Future for Either<A, B>

where A: Future, B: Future<Output = <A as Future>::Output>,

type Output = <A as Future>::Output

The type of value produced on completion.

fn poll( self: Pin<&mut Either<A, B>>, cx: &mut Context<'_>, ) -> Poll<<Either<A, B> as Future>::Output>

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

impl<A, B> Hash for Either<A, B>

where A: Hash, B: Hash,

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<A, B> Ord for Either<A, B>

where A: Ord, B: Ord,

fn cmp(&self, other: &Either<A, B>) -> Ordering

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<A, B> PartialEq for Either<A, B>

where A: PartialEq, B: PartialEq,

fn eq(&self, other: &Either<A, B>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<A, B> PartialOrd for Either<A, B>

where A: PartialOrd, B: PartialOrd,

fn partial_cmp(&self, other: &Either<A, B>) -> Option<Ordering>

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

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

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

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

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

impl<St, A, B> Responder<St> for Either<A, B>

where St: State, A: Responder<St>, B: Responder<St>,

Combines two different responder types into a single type

use ntex::{web::HttpResponse, util::Either};

fn index() -> Either<HttpResponse, &'static str> {
    if is_a_variant() {
        // <- choose left variant
        Either::Left(HttpResponse::BadRequest().body("Bad data"))
    } else {
        // <- Right variant
        Either::Right("Hello!")
    }
}

async fn respond_to(self, st: &St, req: &HttpRequest) -> Response

Builds an HTTP response from this value.

fn with_status(self, status: StatusCode) -> CustomResponder<Self, St>

where Self: Sized,

Replaces the status code produced by this responder.

fn with_header<K, V>(self, key: K, value: V) -> CustomResponder<Self, St>

where Self: Sized, HeaderName: TryFrom<K>, HeaderValue: TryFrom<V>, <HeaderName as TryFrom<K>>::Error: Into<HttpError>, <HeaderValue as TryFrom<V>>::Error: Into<HttpError>,

Sets a header on the response produced by this responder.

impl<A, B, St, Req> Service<St, Req> for Either<A, B>

where A: Service<St, Req>, B: Service<St, Req, Res = <A as Service<St, Req>>::Res, Error = <A as Service<St, Req>>::Error>,

type Res = <A as Service<St, Req>>::Res

Response produced by the service.

type Error = <A as Service<St, Req>>::Error

Error produced while checking readiness or processing a request.

async fn call( &self, req: Req, ctx: Ctx<'_, Either<A, B>, St>, ) -> Result<<Either<A, B> as Service<St, Req>>::Res, <Either<A, B> as Service<St, Req>>::Error>

Processes a request and asynchronously returns the response.

async fn ready( &self, ctx: Ctx<'_, Either<A, B>, St>, ) -> Result<(), <Either<A, B> as Service<St, Req>>::Error>

Waits until the service is ready to process a request.

async fn shutdown(&self, ctx: Ctx<'_, Either<A, B>, St>)

Shuts down the service.

fn map<F, Res>(self, f: F) -> ServiceChain<Map<F, Self, Res>, St, Req>

where Self: Sized, F: Fn(Self::Res) -> Res,

Maps this service’s output to a different type, returning a new service.

fn map_err<F, E>(self, f: F) -> ServiceChain<MapErr<F, Self, E>, St, Req>

where Self: Sized, F: Fn(Self::Error) -> E,

Maps this service’s error to a different type, returning a new service.

fn and_then<Next, F>(self, f: F) -> ServiceChain<AndThen<Self, Next>, St, Req>

where Self: Sized, Next: Service<St, Self::Res, Error = Self::Error>, F: IntoService<Next, St, Self::Res>,

Calls another service after this service completes successfully.

fn pipeline(self, st: St) -> Pipeline<Req, Self::Res, Self::Error>

where Self: Sized + 'static, St: 'static, Req: 'static,

Wraps this service and its state in a Pipeline.

impl<A, B> StructuralPartialEq for Either<A, B>

where A: PartialEq, B: PartialEq,

impl<St, Err, A, B> WebResponseError<St, Err> for Either<A, B>

where A: WebResponseError<St, Err>, B: WebResponseError<St, Err>,

fn error_response(&self, st: &St) -> HttpResponse

Generate response for error

fn into(self) -> Box<dyn WebResponseError<St, Err>>

where Self: Sized,

Convert the error into a boxed trait object.