Struct LayoutFingerprint 

pub struct LayoutFingerprint { /* private fields */ }

An 8-byte deterministic layout fingerprint.

Generated from SHA-256("hopper:v1:" + name + ":" + version + ":" + fields)[..8]. Two layouts with identical fields, types, sizes, and ordering produce the same fingerprint. Any structural change produces a different one.

Use this to assert compatibility between layout versions at compile time, verify on-chain accounts match expected schemas, and detect schema drift in migration paths.

Implementations

impl LayoutFingerprint

pub const fn from_bytes(bytes: [u8; 8]) -> Self

Create a fingerprint from raw bytes.

pub const fn as_bytes(&self) -> &[u8; 8]

Raw fingerprint bytes.

pub const fn matches(&self, other: &LayoutFingerprint) -> bool

Check if two fingerprints match.

pub const fn differs_from(&self, other: &LayoutFingerprint) -> bool

Check if two fingerprints differ (schema changed between versions).

pub fn verify_header(&self, data: &[u8]) -> Result<(), ProgramError>

Verify this fingerprint matches data read from an account header.

Reads the layout_id from bytes 4..12 of the header and compares.

Trait Implementations

impl Clone for LayoutFingerprint

fn clone(&self) -> LayoutFingerprint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl PartialEq for LayoutFingerprint

fn eq(&self, other: &LayoutFingerprint) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for LayoutFingerprint

impl Eq for LayoutFingerprint

impl StructuralPartialEq for LayoutFingerprint