Module spec 

Per-transition preconditions and predictions (§8 TransitionSpec, the pure half). Shared by the diagnoser, which builds proposals, and the executor, which checks that a proposal’s expected refines predict (§12 step 3). Derivation of facts needs the evaluated generation and lives in exec.

Constants

DEFAULT_SETTLE

READY_TIMEOUT

Functions

dependents

Units with a Requires edge to unit, transitively: systemd stops or restarts them along with it.

precondition

predict

What the transition is expected to achieve. For generation operations the set of units that may change is only known after evaluation; predict leaves may_change empty with others_unchanged = false, and the executor bounds it by the derived affected_units instead.

refines

§12 step 3: claimed must agree with predicted on every unit the prediction names, must not broaden may_change, and must not relax others_unchanged. For generation operations (others_unchanged = false in the prediction) bound limits may_change instead.