Trait AccountLayout 

pub trait AccountLayout: WireLayout {
    const DISC: u8;
    const VERSION: u8;
    const WIRE_FINGERPRINT: u64;
    const TYPE_OFFSET: usize;
    const SCHEMA_EPOCH: u32 = 1;

    // Provided method
    fn required_len() -> usize { ... }
}

Hopper account layout identity, the top of the unified trait stack.

WIRE_FINGERPRINT is the first 8 bytes of the canonical SHA-256 wire descriptor emitted by the #[hopper::state] expansion in the hopper-derive package, reinterpreted as a little-endian u64, so the runtime can compare against the on-account header byte-for-byte.

SCHEMA_EPOCH defaults to 1; programs that publish later epochs via their on-chain manifest bump it to signal a version transition.

Required Associated Constants

const DISC: u8

On-chain discriminator (header byte 0).

const VERSION: u8

Layout version (header byte 1).

const WIRE_FINGERPRINT: u64

Canonical wire fingerprint (header bytes 4..12, little-endian).

const TYPE_OFFSET: usize

Offset at which Self starts inside the account buffer. 0 for header-inclusive layouts, HEADER_LEN for body-only.

Provided Associated Constants

const SCHEMA_EPOCH: u32 = 1

Schema-evolution epoch (header bytes 12..16).

Provided Methods

fn required_len() -> usize

Total data length an account must carry to hold Self.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<T: LayoutContract + ZeroCopy> AccountLayout for T

const DISC: u8 = <T as LayoutContract>::DISC

const VERSION: u8 = <T as LayoutContract>::VERSION

const WIRE_FINGERPRINT: u64

const SCHEMA_EPOCH: u32 = <T as LayoutContract>::SCHEMA_EPOCH

const TYPE_OFFSET: usize = <T as LayoutContract>::TYPE_OFFSET