Struct LazyConfig 

pub struct LazyConfig<T: Copy + Send + Sync + 'static> { /* private fields */ }

Implementations

impl<T: Copy + Send + Sync + 'static> LazyConfig<T>

pub fn create(path: impl AsRef<Path>) -> Result<Self, LazyConfigError>

pub fn open(path: impl AsRef<Path>) -> Result<Self, LazyConfigError>

pub fn try_get(&self) -> Option<T>

Fast path: returns the value when loaded, otherwise None.

pub fn is_loaded(&self) -> bool

True when the config has been loaded.

pub fn get_or_fetch<F: FnOnce() -> T>(&self, fetcher: F) -> T

Get the value if cached. Otherwise, race to be the canonical fetcher: the CAS winner runs fetcher and publishes; CAS losers block until the winner publishes, then return the canonical value.

Across all processes mapping this file, fetcher runs at most once per process AND only one process’s result becomes canonical. (In practice with the CAS-then-fetch protocol from SharedOnceCell::get_or_init, the winner is the only one to actually run the fetcher.)

pub fn force_set(&self, value: T) -> bool

Force-set the value without going through a fetcher. Useful for testing or for an admin-set-config workflow. Returns true if this caller’s value became canonical (it won the CAS), false when the cell was already initialised.

pub fn flush(&self) -> Result<(), LazyConfigError>

pub fn flush_async(&self) -> Result<(), LazyConfigError>

Non-blocking flush: schedules a writeback via the OS. Note: Windows is only partially async (sync to page cache, not to disk).

Trait Implementations

impl<T: Copy + Send + Sync + 'static> AdaptiveInstance for LazyConfig<T>

fn header(&self) -> &HandshakeHeader

fn ring(&self) -> &ObservationRing

fn make_policy(&self) -> Box<dyn Policy>

fn apply_migration(&self, new_tag: u32)

Called by the sidecar when the policy returns a new strategy tag. Default implementation: just set the tag on the header. Primitives that need heavier migration (data-layout swap) override this to perform the swap before (or after) updating the tag.