Objects Namespace

To maintain compatibility with the EVM, Move objects are organized within a global storage layout. Conceptually, the storage can be represented by the following Solidity mapping:

// Conceptually: owner => object_id => object_data
mapping(bytes32 => mapping(bytes32 => Object<T>)) public Objects;

This nested approach serves two primary purposes:

• Ownership Partitioning: The outer mapping is keyed by the owner identifier. This can be an account address or an object UID (or precomputed NamedId) in the case of wrapped objects.

• Object Retrieval: The inner mapping is keyed by the unique Object UID (or precomputed NamedId), ensuring that data for specific assets can be retrieved effortlessly.

Important

The data organized this way naturally prevents unauthorized access, as each account or object can only access its own namespace unless explicitly allowed (e.g., via the Peep API).

Note

The mapping itself is stored at a specific slot, the slot 0.

Handling different ownership types

The framework distinguishes between different object lifecycles by routing them to specific owner keys within the mapping. This design allows the runtime to handle owned, shared, and frozen objects under a single consistent logic:

By utilizing 0x1 and 0x2 as fixed keys, the framework ensures these states are globally unique and easily handled.

Type Safety and Validation

To enforce strict type safety, the framework prevents “type-casting” at the storage level. Every object’s data blob begins with a Type Hash header:

• Offset 0-8: Stores a 64-bit Type hash derived from the Move struct definition.

• Offset 8: Contains the actual serialized fields of the object.

When a contract attempts to peep or load an object, the runtime first verifies that the hash in storage matches the hash of the Move type specified in the code. If they don’t match, the transaction reverts.

The following section provides a detailed overview of the storage layout, including how different data types are encoded and stored within this framework.