Function get_field_optional 

pub fn get_field_optional<T: CurrentTxFieldGetter, const CODE: i32>(
    field: SField<T, CODE>,
) -> Result<Option<T>>

Retrieves an optionally present field from the current transaction using an SField constant.

Arguments

• field - An SField constant that encodes both the field code and expected type

Returns

Returns a Result<Option<T>> where:

• Ok(Some(T)) - The field value for the specified field
• Ok(None) - If the field is not present (i.e., result_code == FIELD_NOT_FOUND)
• Err(Error) - If the field cannot be retrieved or has unexpected size

Example

use xrpl_wasm_stdlib::core::current_tx::get_field_optional;
use xrpl_wasm_stdlib::sfield;

// Type is automatically inferred from the SField constant
let flags = get_field_optional(sfield::Flags).unwrap();  // Option<u32>
let source_tag = get_field_optional(sfield::SourceTag).unwrap();  // Option<u32>