Struct FieldExtractor 

pub struct FieldExtractor { /* private fields */ }

Facilitates the extraction of a scalar value from a specified field within a Serializeable struct.

This struct holds the configuration for the extraction, namely the target field name. The primary way to use this is via the associated function FieldExtractor::evaluate.

Implementations

impl FieldExtractor

pub fn new<S: Into<String>>(field_name: S) -> Self

Creates a new FieldExtractor configured to target the specified field name.

Accepts any type that can be converted into a String, such as &str.

pub fn evaluate<T: Serialize>( &self, record: &T, ) -> Result<FieldScalarValue, EvaluateError>

Extracts the scalar value of the configured field_name from the given record.

This method drives the custom serialization process to capture the field’s value.

Arguments

• record: A reference to a struct that implements serde::Serialize.

Errors

Returns EvaluateError if:

• The field_name is not found in the record (EvaluateError::FieldNotFound).
• The field_name’s value is not a supported scalar type (EvaluateError::UnsupportedType).
• Any other Serde serialization error occurs.

Trait Implementations

impl Clone for FieldExtractor

fn clone(&self) -> FieldExtractor

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FieldExtractor

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

Formats the value using the given formatter.