unmarshaled

Unmarshaled is a term used in computing to describe data that has been converted from a serialized representation back into an in-memory data structure. The process is the counterpart of marshaling, which converts in-memory objects into a portable format for storage or transmission.

In practice, unmarshaled data results from applying a deserialization routine, often named Unmarshal or similar in the surrounding language. Languages such as Go, Java, Python, and others provide standard libraries that perform unmarshalling from formats like JSON or XML.

Common input formats include JSON, XML, YAML, and Protocol Buffers. Unmarshaling involves parsing the input, validating its structure, and populating the fields of a target data type, including nested objects and collections. Some libraries support streaming unmarshalling for large payloads.

Security and correctness are important considerations. Deserializing data from untrusted sources can open risks such as code execution or data corruption if schemas are mismatched or unsafe types are allowed. Best practices include schema validation, strict mode, versioning, and using safe deserializers.

See also deserialization, marshaling, serialization.