Enum SurrogatePolicy 

pub enum SurrogatePolicy {
    Reject,
    ReplaceWithFFFD,
    Skip,
}

Policy for handling unpaired UTF-16 surrogates in JSON input

JSON’s \uXXXX escapes use UTF-16 encoding. Characters outside the Basic Multilingual Plane (U+10000+, including emoji) require surrogate pairs: a high surrogate (0xD800-0xDBFF) followed immediately by a low surrogate (0xDC00-0xDFFF).

Some systems (e.g., JavaScript with truncated strings, legacy databases) may emit unpaired surrogates, which are technically invalid Unicode but may appear in real-world data.

Example

use hedl_json::{FromJsonConfig, SurrogatePolicy};

// Default: reject unpaired surrogates
let strict = FromJsonConfig::default();

// Replace unpaired surrogates with U+FFFD
let lenient = FromJsonConfig::builder()
    .surrogate_policy(SurrogatePolicy::ReplaceWithFFFD)
    .build();

// Skip (remove) unpaired surrogates entirely
let skip = FromJsonConfig::builder()
    .surrogate_policy(SurrogatePolicy::Skip)
    .build();

Variants

Reject

Reject unpaired surrogates with an error (default, strict)

This is the safest option and ensures all processed JSON contains valid Unicode. Use this for data integrity requirements.

ReplaceWithFFFD

Replace unpaired surrogates with U+FFFD (replacement character)

This allows processing of JSON with invalid Unicode while preserving string structure. The replacement character (�) signals data loss.

Skip

Skip (remove) unpaired surrogates silently

Use with caution: this modifies string content without indication. Suitable when the surrogates are known to be noise or artifacts.

Trait Implementations

impl Clone for SurrogatePolicy

fn clone(&self) -> SurrogatePolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SurrogatePolicy

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

Formats the value using the given formatter.

impl Default for SurrogatePolicy

fn default() -> SurrogatePolicy

Returns the “default value” for a type.

impl PartialEq for SurrogatePolicy

fn eq(&self, other: &SurrogatePolicy) -> 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 Copy for SurrogatePolicy

impl Eq for SurrogatePolicy

impl StructuralPartialEq for SurrogatePolicy