def observed

bendvy-ecs-core@0.1.0.4 · ordinary_machine_condition.bend:17

import Base
import bendvy-ecs-core@0.1.0.4/ordinary_machine_initialization.bend as Init
import bendvy-ecs-core@0.1.0.4/world.bend as W
import bendvy-ecs-core@0.1.0.4/system.bend as Sys

17def observed(~S:Data,~K:Data,~V:Data,~R:Type,~take:R -> R & Init.State<S,K,V>,~put:R -> Init.State<S,K,V> -> R,~C:Type,~E:Data,prior:Nat,pair:W.World<S,C,R,E> & (Nat & Bool)) -> Sys.Outcome<W.World<S,C,R,E>,Unit,Nat & Bool>:
18  match pair:
19    case (world,(+current,present)):Sys.Succeeded{world,(current,Bool.and(present,Nat.is_lt(prior,current)))}