Is Go\'s encoding/gob Deterministic, and If Not, Under What Conditions?

Determinism in Encoding/gob

The encoding/gob package in Go enables object serialization to a stream of bytes. This package is often used for data exchange across processes or network communication. A fundamental question arises: is the output of encoding/gob deterministic?

Current implementations of encoding/gob, as of this discussion, produce deterministic results. However, this determinism is not absolute.

Non-Determinism Due to Interface and Map Iteration

The original question assumes no usage of interfaces or maps. However, when encoding/gob encounters maps, non-determinism can arise. This is due to the random order of iteration for maps, resulting in varying serialization order of their elements.

Determinism with Type References

Encoding/gob uses type references to minimize the size of the encoded stream. When encountering a new type, its specification is sent. For subsequent values of the same type, only a reference to the previous type specification is included. This results in varying output depending on the first occurrence of a particular type.

Consistency with Multiple Encoders

While encoding/gob's output may vary among different Go versions, it remains consistent when using the same gob.Encoder for a particular set of values. This ensures that data can be decoded correctly as long as the same version of Go is used.

The above is the detailed content of Is Go\'s encoding/gob Deterministic, and If Not, Under What Conditions?. For more information, please follow other related articles on the PHP Chinese website!