Function parse_record_from_shared_bytes 

pub fn parse_record_from_shared_bytes(
    record_bytes: &Arc<Vec<u8>>,
    recovery_mode: RecoveryMode,
    validation_level: ValidationLevel,
) -> Result<Option<Record>>

Parse one complete MARC record from a buffer the caller already holds behind a shared Arc, without taking ownership of the bytes.

Identical in behavior to parse_record_from_bytes, but lets a caller that must retain the record bytes after parsing — for example to expose pymarc’s current_chunk — share a single allocation between the parser and its own state instead of cloning. The parser borrows the buffer; the caller keeps its Arc handle alive for as long as it needs the bytes.

Errors

Same as parse_record_from_bytes: malformed bytes yield an error (in Strict mode the first structural defect; in recovery modes only unrecoverable ones).