Struct serde_with::TryFromInto [−][src]
pub struct TryFromInto<T>(_);
Serialize value by converting to/from a proxy type with serde support.
This adapter serializes a type O
by converting it into a second type T
and serializing T
.
Deserializing works analogue, by deserializing a T
and then converting into O
.
struct S { #[serde_as(as = "TryFromInto<T>")] value: O, }
For serialization O
needs to be O: TryInto<T> + Clone
.
For deserialization the opposite T: TryInto<O>
is required.
The Clone
bound is required since serialize
operates on a reference but TryInto
implementations on references are uncommon.
In both cases the TryInto::Error
type must implement Display
.
Note: FromInto
is the more specialized version of this adapter which uses the infallible Into
trait instead.
TryFromInto
is strictly more general and can also be used where FromInto
is applicable.
The example shows a use case, when only the deserialization behavior is fallible, but not serializing.
Example
#[derive(Clone, Debug, PartialEq)] enum Boollike { True, False, } impl From<Boollike> for u8 { ... } impl TryFrom<u8> for Boollike { type Error = String; fn try_from(v: u8) -> Result<Self, Self::Error> { match v { 0 => Ok(Boollike::False), 1 => Ok(Boollike::True), _ => Err(format!("Boolikes can only be constructed from 0 or 1 but found {}", v)) } } } #[serde_as] #[derive(Deserialize, Serialize)] struct Data { #[serde_as(as = "TryFromInto<u8>")] b: Boollike, } let data = Data { b: Boollike::True, }; // Define our expected JSON form let j = json!({ "b": 1, }); // Ensure serialization and deserialization produce the expected results assert_eq!(j, serde_json::to_value(&data).unwrap()); assert_eq!(data, serde_json::from_value(j).unwrap()); // Numbers besides 0 or 1 should be an error let j = json!({ "b": 2, }); assert_eq!("Boolikes can only be constructed from 0 or 1 but found 2", serde_json::from_value::<Data>(j).unwrap_err().to_string());
Trait Implementations
impl<T: Clone> Clone for TryFromInto<T>
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impl<T: Clone> Clone for TryFromInto<T>
[src]fn clone(&self) -> TryFromInto<T>
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fn clone(&self) -> TryFromInto<T>
[src]Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)
1.0.0[src]
fn clone_from(&mut self, source: &Self)
1.0.0[src]Performs copy-assignment from source
. Read more
impl<T: Debug> Debug for TryFromInto<T>
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impl<T: Debug> Debug for TryFromInto<T>
[src]impl<T: Default> Default for TryFromInto<T>
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impl<T: Default> Default for TryFromInto<T>
[src]fn default() -> TryFromInto<T>
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fn default() -> TryFromInto<T>
[src]Returns the “default value” for a type. Read more
impl<'de, T, U> DeserializeAs<'de, T> for TryFromInto<U> where
U: TryInto<T>,
<U as TryInto<T>>::Error: Display,
U: Deserialize<'de>,
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impl<'de, T, U> DeserializeAs<'de, T> for TryFromInto<U> where
U: TryInto<T>,
<U as TryInto<T>>::Error: Display,
U: Deserialize<'de>,
[src]fn deserialize_as<D>(deserializer: D) -> Result<T, D::Error> where
D: Deserializer<'de>,
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fn deserialize_as<D>(deserializer: D) -> Result<T, D::Error> where
D: Deserializer<'de>,
[src]Deserialize this value from the given Serde deserializer.
impl<T, U> SerializeAs<T> for TryFromInto<U> where
T: TryInto<U> + Clone,
<T as TryInto<U>>::Error: Display,
U: Serialize,
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impl<T, U> SerializeAs<T> for TryFromInto<U> where
T: TryInto<U> + Clone,
<T as TryInto<U>>::Error: Display,
U: Serialize,
[src]fn serialize_as<S>(source: &T, serializer: S) -> Result<S::Ok, S::Error> where
S: Serializer,
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fn serialize_as<S>(source: &T, serializer: S) -> Result<S::Ok, S::Error> where
S: Serializer,
[src]Serialize this value into the given Serde serializer.
impl<T: Copy> Copy for TryFromInto<T>
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Auto Trait Implementations
impl<T> RefUnwindSafe for TryFromInto<T> where
T: RefUnwindSafe,
T: RefUnwindSafe,
impl<T> Send for TryFromInto<T> where
T: Send,
T: Send,
impl<T> Sync for TryFromInto<T> where
T: Sync,
T: Sync,
impl<T> Unpin for TryFromInto<T> where
T: Unpin,
T: Unpin,
impl<T> UnwindSafe for TryFromInto<T> where
T: UnwindSafe,
T: UnwindSafe,
Blanket Implementations
impl<T> BorrowMut<T> for T where
T: ?Sized,
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impl<T> BorrowMut<T> for T where
T: ?Sized,
[src]pub fn borrow_mut(&mut self) -> &mut T
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pub fn borrow_mut(&mut self) -> &mut T
[src]Mutably borrows from an owned value. Read more
impl<T> ToOwned for T where
T: Clone,
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impl<T> ToOwned for T where
T: Clone,
[src]type Owned = T
type Owned = T
The resulting type after obtaining ownership.
pub fn to_owned(&self) -> T
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pub fn to_owned(&self) -> T
[src]Creates owned data from borrowed data, usually by cloning. Read more
pub fn clone_into(&self, target: &mut T)
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pub fn clone_into(&self, target: &mut T)
[src]🔬 This is a nightly-only experimental API. (toowned_clone_into
)
recently added
Uses borrowed data to replace owned data, usually by cloning. Read more