Type Alias Outcome

pub type Outcome<S, E> = Outcome<S, (Status, E), Status>;

Type alias for the Outcome of a FromRequest conversion.

Aliased Type

enum Outcome<S, E> {
    Success(S),
    Error((Status, E)),
    Forward(Status),
}

Variants

Success(S)

Contains the success value.

Error((Status, E))

Contains the error error value.

Forward(Status)

Contains the value to forward on.

Implementations

impl<S, E, F> Outcome<S, E, F>

pub fn unwrap(self) -> S

Unwraps the Outcome, yielding the contents of a Success.

Panics

Panics if the value is not Success.

Examples

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.unwrap(), 10);

pub fn expect(self, message: &str) -> S

Unwraps the Outcome, yielding the contents of a Success.

Panics

If the value is not Success, panics with the given message.

Examples

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.expect("success value"), 10);

pub fn is_success(&self) -> bool

Return true if this Outcome is a Success.

Examples

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.is_success(), true);

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.is_success(), false);

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.is_success(), false);

pub fn is_error(&self) -> bool

Return true if this Outcome is an Error.

Examples

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.is_error(), false);

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.is_error(), true);

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.is_error(), false);

pub fn is_forward(&self) -> bool

Return true if this Outcome is a Forward.

Examples

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.is_forward(), false);

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.is_forward(), false);

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.is_forward(), true);

pub fn succeeded(self) -> Option<S>

Converts from Outcome<S, E, F> to Option<S>.

Returns the Some of the Success if this is a Success, otherwise returns None. self is consumed, and all other values are discarded.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.succeeded(), Some(10));

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.succeeded(), None);

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.succeeded(), None);

pub fn failed(self) -> Option<E>

Converts from Outcome<S, E, F> to Option<E>.

Returns the Some of the Error if this is an Error, otherwise returns None. self is consumed, and all other values are discarded.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.failed(), None);

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.failed(), Some("Hi! I'm an error."));

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.failed(), None);

pub fn forwarded(self) -> Option<F>

Converts from Outcome<S, E, F> to Option<F>.

Returns the Some of the Forward if this is a Forward, otherwise returns None. self is consumed, and all other values are discarded.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.forwarded(), None);

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.forwarded(), None);

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.forwarded(), Some(25));

pub fn success_or<T>(self, value: T) -> Result<S, T>

Returns a Success value as Ok() or value in Err. Converts from Outcome<S, E, F> to Result<S, T> for a given T.

Returns Ok with the Success value if this is a Success, otherwise returns an Err with the provided value. self is consumed, and all other values are discarded.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.success_or(false), Ok(10));

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.success_or(false), Err(false));

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.success_or("whoops"), Err("whoops"));

pub fn success_or_else<T, V: FnOnce() -> T>(self, f: V) -> Result<S, T>

Returns a Success value as Ok() or f() in Err. Converts from Outcome<S, E, F> to Result<S, T> for a given T produced from a supplied function or closure.

Returns Ok with the Success value if this is a Success, otherwise returns an Err with the result of calling f. self is consumed, and all other values are discarded.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.success_or_else(|| false), Ok(10));

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.success_or_else(|| false), Err(false));

let x: Outcome<i32, &str, usize> = Forward(25);
assert_eq!(x.success_or_else(|| "whoops"), Err("whoops"));

pub fn as_ref(&self) -> Outcome<&S, &E, &F>

Converts from Outcome<S, E, F> to Outcome<&S, &E, &F>.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.as_ref(), Success(&10));

let x: Outcome<i32, &str, usize> = Error("Hi! I'm an error.");
assert_eq!(x.as_ref(), Error(&"Hi! I'm an error."));

pub fn as_mut(&mut self) -> Outcome<&mut S, &mut E, &mut F>

Converts from Outcome<S, E, F> to Outcome<&mut S, &mut E, &mut F>.

let mut x: Outcome<i32, &str, usize> = Success(10);
if let Success(val) = x.as_mut() {
    *val = 20;
}

assert_eq!(x.unwrap(), 20);

pub fn map<T, M: FnOnce(S) -> T>(self, f: M) -> Outcome<T, E, F>

Maps the Success value using f. Maps an Outcome<S, E, F> to an Outcome<T, E, F> by applying the function f to the value of type S in self if self is an Outcome::Success.

let x: Outcome<i32, &str, usize> = Success(10);

let mapped = x.map(|v| if v == 10 { "10" } else { "not 10" });
assert_eq!(mapped, Success("10"));

pub fn map_error<T, M: FnOnce(E) -> T>(self, f: M) -> Outcome<S, T, F>

Maps the Error value using f. Maps an Outcome<S, E, F> to an Outcome<S, T, F> by applying the function f to the value of type E in self if self is an Outcome::Error.

let x: Outcome<i32, &str, usize> = Error("hi");

let mapped = x.map_error(|v| if v == "hi" { 10 } else { 0 });
assert_eq!(mapped, Error(10));

pub fn map_forward<T, M: FnOnce(F) -> T>(self, f: M) -> Outcome<S, E, T>

Maps the Forward value using f. Maps an Outcome<S, E, F> to an Outcome<S, E, T> by applying the function f to the value of type F in self if self is an Outcome::Forward.

let x: Outcome<i32, &str, usize> = Forward(5);

let mapped = x.map_forward(|v| if v == 5 { "a" } else { "b" });
assert_eq!(mapped, Forward("a"));

pub fn and_then<T, M: FnOnce(S) -> Outcome<T, E, F>>( self, f: M, ) -> Outcome<T, E, F>

Converts from Outcome<S, E, F> to Outcome<T, E, F> using f to map Success(S) to Success(T).

If self is not Success, self is returned.

Examples

let x: Outcome<i32, &str, bool> = Success(10);

let mapped = x.and_then(|v| match v {
   10 => Success("10"),
   1 => Forward(false),
   _ => Error("30")
});

assert_eq!(mapped, Success("10"));

pub fn error_then<T, M: FnOnce(E) -> Outcome<S, T, F>>( self, f: M, ) -> Outcome<S, T, F>

Converts from Outcome<S, E, F> to Outcome<S, T, F> using f to map Error(E) to Error(T).

If self is not Error, self is returned.

Examples

let x: Outcome<i32, &str, bool> = Error("hi");

let mapped = x.error_then(|v| match v {
   "hi" => Error(10),
   "test" => Forward(false),
   _ => Success(10)
});

assert_eq!(mapped, Error(10));

pub fn forward_then<T, M: FnOnce(F) -> Outcome<S, E, T>>( self, f: M, ) -> Outcome<S, E, T>

Converts from Outcome<S, E, F> to Outcome<S, E, T> using f to map Forward(F) to Forward(T).

If self is not Forward, self is returned.

Examples

let x: Outcome<i32, &str, Option<bool>> = Forward(Some(false));

let mapped = x.forward_then(|v| match v {
   Some(true) => Success(10),
   Some(false) => Forward(20),
   None => Error("10")
});

assert_eq!(mapped, Forward(20));

pub fn ok_map_forward<M>(self, f: M) -> Result<S, E>

where M: FnOnce(F) -> Result<S, E>,

Converts Outcome<S, E, F> to Result<S, E> by identity mapping Success(S) and Error(E) to Result<T, E> and mapping Forward(F) to Result<T, E> using f.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.ok_map_forward(|x| Ok(x as i32 + 1)), Ok(10));

let x: Outcome<i32, &str, usize> = Error("hello");
assert_eq!(x.ok_map_forward(|x| Ok(x as i32 + 1)), Err("hello"));

let x: Outcome<i32, &str, usize> = Forward(0);
assert_eq!(x.ok_map_forward(|x| Ok(x as i32 + 1)), Ok(1));

pub fn ok_map_error<M>(self, f: M) -> Result<S, F>

where M: FnOnce(E) -> Result<S, F>,

Converts Outcome<S, E, F> to Result<S, E> by identity mapping Success(S) and Forward(F) to Result<T, F> and mapping Error(E) to Result<T, F> using f.

let x: Outcome<i32, &str, usize> = Success(10);
assert_eq!(x.ok_map_error(|s| Ok(123)), Ok(10));

let x: Outcome<i32, &str, usize> = Error("hello");
assert_eq!(x.ok_map_error(|s| Ok(123)), Ok(123));

let x: Outcome<i32, &str, usize> = Forward(0);
assert_eq!(x.ok_map_error(|s| Ok(123)), Err(0));

impl<'a, S: Send + 'a, E: Send + 'a, F: Send + 'a> Outcome<S, E, F>

pub fn pin(self) -> BoxFuture<'a, Self>

Pins a future that resolves to self, returning a BoxFuture that resolves to self.

Trait Implementations

impl<'r, T: FromRequest<'r>> FromRequest<'r> for Outcome<T, T::Error>

type Error = Infallible

The associated error to be returned if derivation fails.

fn from_request<'life0, 'async_trait>( request: &'r Request<'life0>, ) -> Pin<Box<dyn Future<Output = Outcome<Self, Infallible>> + Send + 'async_trait>>

where Self: 'async_trait, 'r: 'async_trait, 'life0: 'async_trait,

Derives an instance of Self from the incoming request metadata.

impl<S: Clone, E: Clone, F: Clone> Clone for Outcome<S, E, F>

fn clone(&self) -> Outcome<S, E, F>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<S, E, F> Debug for Outcome<S, E, F>

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

Formats the value using the given formatter.

impl<S, E, F> Display for Outcome<S, E, F>

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

Formats the value using the given formatter.

impl<S: Hash, E: Hash, F: Hash> Hash for Outcome<S, E, F>

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

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<S: Ord, E: Ord, F: Ord> Ord for Outcome<S, E, F>

fn cmp(&self, other: &Outcome<S, E, F>) -> 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<S: PartialEq, E: PartialEq, F: PartialEq> PartialEq for Outcome<S, E, F>

fn eq(&self, other: &Outcome<S, E, F>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<S: PartialOrd, E: PartialOrd, F: PartialOrd> PartialOrd for Outcome<S, E, F>

fn partial_cmp(&self, other: &Outcome<S, E, F>) -> 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<S: Copy, E: Copy, F: Copy> Copy for Outcome<S, E, F>

impl<S: Eq, E: Eq, F: Eq> Eq for Outcome<S, E, F>

impl<S, E, F> StructuralPartialEq for Outcome<S, E, F>