Enum UnknownFields 

#[non_exhaustive]
pub enum UnknownFields {
    Ignore,
    Error,
    Collect(IgnoredFields),
}

What happens with keys of structs that no field takes.

Derived structs ignore keys they do not know by default. This policy changes that for all structs of a deserialization, while #[deser(deny_unknown_fields)] rejects unknown keys for a single type regardless of the policy. It’s an extension value, usually configured in the Context (or in the State of a single deserialization, see set). To collect the unknown keys of a single deserialization see IgnoredFields.

Only the struct that the key is given to decides: flattened fields are asked if they take a key first (see value_for_key), so a key is only unknown if neither the struct nor any of its flattened fields take it.

use deser::de::UnknownFields;
use deser::{Context, Deserialize};

#[derive(Deserialize, Debug)]
struct Config {
    name: String,
}

let config = deser_json::DeserializerConfig::builder()
    .context(Context::with(UnknownFields::Error))
    .build();
let err = config
    .from_str::<Config>(r#"{"name": "demo", "nmae": "demo"}"#)
    .unwrap_err();
assert_eq!(err.message(), "unknown field `nmae`, expected `name`");

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Ignore

Unknown keys are ignored.

Error

Unknown keys are rejected.

Collect(IgnoredFields)

Unknown keys are ignored but reported to a IgnoredFields.

The collector is shared, so this is meant for a single deserialization (see IgnoredFields).

Implementations

impl UnknownFields

pub fn of(state: &State) -> &UnknownFields

Returns the policy of a deserialization.

pub fn set(self, state: &mut State)

Sets the policy of a deserialization.

Trait Implementations

impl Clone for UnknownFields

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for UnknownFields

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

Formats the value using the given formatter.

impl Default for UnknownFields

fn default() -> Self

Returns the “default value” for a type.