Enum MigrationPolicy 

pub enum MigrationPolicy {
    NoOp,
    AppendOnly,
    RequiresMigration,
    Incompatible,
}

Migration policy for a version transition.

Variants

NoOp

No changes – manifests are identical.

AppendOnly

Append-only: new fields added at end. Existing data valid as-is. Just update header (version + layout_id). No data movement needed.

RequiresMigration

Migration required: field types/sizes changed, or fields removed. Must allocate new account, copy compatible prefix, zero-init new region.

Incompatible

Incompatible: different discriminators or fundamental layout mismatch.

Trait Implementations

impl Clone for MigrationPolicy

fn clone(&self) -> MigrationPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MigrationPolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for MigrationPolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for MigrationPolicy

fn eq(&self, other: &MigrationPolicy) -> 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 MigrationPolicy

impl Eq for MigrationPolicy

impl StructuralPartialEq for MigrationPolicy