Enum JsonDecodeNumberModel 

#[non_exhaustive]
pub enum JsonDecodeNumberModel {
    Integer64,
    Integer64WithFiniteFallback,
}

Controls lexical admission of syntactically valid JSON number tokens.

Typed decoding still lets Serde construct the requested target type, so its numeric representation can depend on that type and the active Serde features. Validated decoding constructs its owned value according to this model and the selected number policy.

Examples

The default model rejects an integer above u64::MAX. The finite fallback admits it as an f64, which rounds this value and loses integer precision. This example uses a controlled input and an unlimited decoder for illustration; use finite limits for untrusted input. Typed decoding still lets the target type and active features determine its representation. Use a string or a domain-specific format when exact large integers are needed. See JsonValidatedDecodeOptions and the JSON number contract.

use std::convert::Infallible;

use qubit_json::decode::JsonDecodeErrorKind;
use qubit_json::decode::JsonDecodeNumberModel;
use qubit_json::decode::JsonDecoder;
use qubit_json::decode::JsonNumberPolicy;
use qubit_json::decode::JsonValidatedDecodeError;
use qubit_json::decode::JsonValidatedDecodeOptions;

let input = "18446744073709551617";
let strict = JsonValidatedDecodeOptions::builder().build();
let error = JsonDecoder::unlimited()
    .decode_unique_validated_str(input, &strict, |_, _| {
        Ok::<_, Infallible>(JsonNumberPolicy::Preserve)
    })
    .expect_err("the default model rejects integers above u64::MAX");
match error {
    JsonValidatedDecodeError::Decode { error, .. } => {
        assert_eq!(error.kind(), JsonDecodeErrorKind::InvalidJson);
    }
    other => panic!("unexpected error: {other:?}"),
}

let fallback = JsonValidatedDecodeOptions::builder()
    .number_model(JsonDecodeNumberModel::Integer64WithFiniteFallback)
    .build();
let owner = JsonDecoder::unlimited()
    .decode_unique_validated_str(input, &fallback, |_, _| {
        Ok::<_, Infallible>(JsonNumberPolicy::Preserve)
    })
    .expect("finite fallback admits the token with rounding");
assert!(owner.as_value().is_f64());
assert_eq!(owner.as_value().as_f64(), Some(18446744073709551616_f64));

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.

Integer64

Accept signed and unsigned 64-bit integers and finite floating values.

Integer64WithFiniteFallback

Also admit out-of-range integer tokens when they convert to finite f64 values.

Validated decoding with JsonNumberPolicy::Preserve materializes these tokens as finite f64; typed decoding leaves their representation to Serde for the requested target type.

Trait Implementations

impl Clone for JsonDecodeNumberModel

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for JsonDecodeNumberModel

impl Debug for JsonDecodeNumberModel

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

Formats the value using the given formatter.

impl Default for JsonDecodeNumberModel

fn default() -> Self

Returns the “default value” for a type.

impl Eq for JsonDecodeNumberModel

impl Hash for JsonDecodeNumberModel

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 PartialEq for JsonDecodeNumberModel

fn eq(&self, other: &Self) -> bool

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for JsonDecodeNumberModel