Summary

Refactored the Felt252Serde trait to use iterators instead of slices for deserialization. This changes the trait's deserialize method signature from returning a tuple of (Self, &[BigUintAsHex]) to just returning Self and taking a mutable iterator of &BigUint references. Also updated the decompress function to return a vector of &BigUint instead of mutating an output vector.

Type of change

• Performance improvement

Why is this change needed?

The current implementation of deserialization passes slices around and returns the remaining slice after each deserialization step. This approach is less efficient and more error-prone than using iterators. The iterator-based approach simplifies the code and makes it more maintainable while potentially improving performance.

What was the behavior or documentation before?

The Felt252Serde trait's deserialize method took a slice of BigUintAsHex and returned a tuple containing the deserialized value and the remaining slice. The decompress function took an output vector parameter that it would mutate with the decompressed values.

What is the behavior or documentation after?

The Felt252Serde trait's deserialize method now takes a mutable iterator of &BigUint references and returns just the deserialized value. The decompress function now returns a vector of &BigUint references instead of mutating an output parameter.

Additional context

A TODO comment was added to validate that changing the version_id_from_felt252s function is acceptable and to make it iterator-based as well in the future.