pub enum Either<A, B> {
Left(A),
Right(B),
}
Expand description
(De)serializes as either a magic value A
or any other deserializable value
B
.
An Either<A, B>
deserializes as either an A
or B
, whichever succeeds
first.
The usual Either
implementation or an “untagged” enum does not allow its
internal values to provide hints to the deserializer. These hints are
required for magic values to work. By contrast, this Either
does provide
the appropriate hints.
Example
use serde::{Serialize, Deserialize};
use figment::{Figment, value::magic::{Either, RelativePathBuf, Tagged}};
#[derive(Debug, PartialEq, Deserialize, Serialize)]
struct Config {
int_or_str: Either<Tagged<usize>, String>,
path_or_bytes: Either<RelativePathBuf, Vec<u8>>,
}
fn figment<A: Serialize, B: Serialize>(a: A, b: B) -> Figment {
Figment::from(("int_or_str", a)).merge(("path_or_bytes", b))
}
let config: Config = figment(10, "/a/b").extract().unwrap();
assert_eq!(config.int_or_str, Either::Left(10.into()));
assert_eq!(config.path_or_bytes, Either::Left("/a/b".into()));
let config: Config = figment("hi", "c/d").extract().unwrap();
assert_eq!(config.int_or_str, Either::Right("hi".into()));
assert_eq!(config.path_or_bytes, Either::Left("c/d".into()));
let config: Config = figment(123, &[1, 2, 3]).extract().unwrap();
assert_eq!(config.int_or_str, Either::Left(123.into()));
assert_eq!(config.path_or_bytes, Either::Right(vec![1, 2, 3].into()));
let config: Config = figment("boo!", &[4, 5, 6]).extract().unwrap();
assert_eq!(config.int_or_str, Either::Right("boo!".into()));
assert_eq!(config.path_or_bytes, Either::Right(vec![4, 5, 6].into()));
let config: Config = Figment::from(figment::providers::Serialized::defaults(Config {
int_or_str: Either::Left(10.into()),
path_or_bytes: Either::Left("a/b/c".into()),
})).extract().unwrap();
assert_eq!(config.int_or_str, Either::Left(10.into()));
assert_eq!(config.path_or_bytes, Either::Left("a/b/c".into()));
let config: Config = Figment::from(figment::providers::Serialized::defaults(Config {
int_or_str: Either::Right("hi".into()),
path_or_bytes: Either::Right(vec![3, 7, 13]),
})).extract().unwrap();
assert_eq!(config.int_or_str, Either::Right("hi".into()));
assert_eq!(config.path_or_bytes, Either::Right(vec![3, 7, 13]));
Variants
Left(A)
The “left” variant.
Right(B)
The “right” variant.
Trait Implementations
impl<'de, 'b, A, B> Deserialize<'de> for Either<A, B> where
'de: 'b,
A: Magic,
B: Deserialize<'b>,
impl<'de, 'b, A, B> Deserialize<'de> for Either<A, B> where
'de: 'b,
A: Magic,
B: Deserialize<'b>,
fn deserialize<D>(
de: D
) -> Result<Either<A, B>, <D as Deserializer<'de>>::Error> where
D: Deserializer<'de>,
fn deserialize<D>(
de: D
) -> Result<Either<A, B>, <D as Deserializer<'de>>::Error> where
D: Deserializer<'de>,
Deserialize this value from the given Serde deserializer. Read more
impl<A, B> Ord for Either<A, B> where
A: Ord,
B: Ord,
impl<A, B> Ord for Either<A, B> where
A: Ord,
B: Ord,
impl<A, B> PartialOrd<Either<A, B>> for Either<A, B> where
A: PartialOrd<A>,
B: PartialOrd<B>,
impl<A, B> PartialOrd<Either<A, B>> for Either<A, B> where
A: PartialOrd<A>,
B: PartialOrd<B>,
fn partial_cmp(&self, other: &Either<A, B>) -> Option<Ordering>
fn partial_cmp(&self, other: &Either<A, B>) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
impl<A, B> Serialize for Either<A, B> where
A: Serialize,
B: Serialize,
impl<A, B> Serialize for Either<A, B> where
A: Serialize,
B: Serialize,
fn serialize<__S>(
&self,
__serializer: __S
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error> where
__S: Serializer,
fn serialize<__S>(
&self,
__serializer: __S
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error> where
__S: Serializer,
Serialize this value into the given Serde serializer. Read more
impl<A, B> Eq for Either<A, B> where
A: Eq,
B: Eq,
impl<A, B> StructuralEq for Either<A, B>
impl<A, B> StructuralPartialEq for Either<A, B>
Auto Trait Implementations
impl<A, B> RefUnwindSafe for Either<A, B> where
A: RefUnwindSafe,
B: RefUnwindSafe,
impl<A, B> Send for Either<A, B> where
A: Send,
B: Send,
impl<A, B> Sync for Either<A, B> where
A: Sync,
B: Sync,
impl<A, B> Unpin for Either<A, B> where
A: Unpin,
B: Unpin,
impl<A, B> UnwindSafe for Either<A, B> where
A: UnwindSafe,
B: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<Q, K> Equivalent<K> for Q where
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Q where
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
sourcefn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
Compare self to key
and return true
if they are equal.
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
sourcefn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
impl<T> IntoCollection<T> for T
impl<T> IntoCollection<T> for T
fn into_collection<A>(self) -> SmallVec<A> where
A: Array<Item = T>,
fn into_collection<A>(self) -> SmallVec<A> where
A: Array<Item = T>,
Converts self
into a collection.
fn mapped<U, F, A>(self, f: F) -> SmallVec<A> where
F: FnMut(T) -> U,
A: Array<Item = U>,
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcefn clone_into(&self, target: &mut T)
fn clone_into(&self, target: &mut T)
toowned_clone_into
)Uses borrowed data to replace owned data, usually by cloning. Read more
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
fn vzip(self) -> V
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more