1	import Base
2	import ./clock_state.bend as Clock
3	import ./deferred_command.bend as Deferred
4	import entity_allocator.bend as Alloc
5	import machine.bend as M
6	import world.bend as W
7	
8	# Closed resource lenses adapt machine slots to the existing actual ECS world.
9	# No component store or affine resource is projected to Data or copied.
10	def take_join(~S: Data,~K: Data,~V: Data,~C: Type,~R: Type,~E: Data,
11	  +ns: U32,allocator:Alloc.Allocator,
12	  store: C,split: R & M.Slot<S,K,V>,+events: List<&2,E>,commands:List<&1,Deferred.Command<W.World<S,C,R,E>>>,
13	  +registrations: List<&2,W.RegistrationMeta>,+nextSystem: U32,+clock:Clock.State
14	) -> W.World<S,C,R,E> & M.Slot<S,K,V>:
15	  (resources,slot)=split
16	  (W.World{ns,allocator,store,resources,events,commands,registrations,nextSystem,clock},slot)
17	
18	def take(~S: Data,~K: Data,~V: Data,~C: Type,~R: Type,~E: Data,
19	  ~take_resource: R -> R & M.Slot<S,K,V>,world: W.World<S,C,R,E>) -> W.World<S,C,R,E> & M.Slot<S,K,V>:
20	  match world:
21	    case W.World{ns,allocator,store,resources,events,commands,registrations,nextSystem,clock}:
22	      take_join(~S,~K,~V,~C,~R,~E,ns,allocator,store,take_resource(resources),events,commands,registrations,nextSystem,clock)
23	
24	def put(~S: Data,~K: Data,~V: Data,~C: Type,~R: Type,~E: Data,
25	  ~put_resource: R -> M.Slot<S,K,V> -> R,world: W.World<S,C,R,E>,slot: M.Slot<S,K,V>) -> W.World<S,C,R,E>:
26	  match world:
27	    case W.World{ns,allocator,store,resources,events,commands,registrations,nextSystem,clock}:
28	      W.World{ns,allocator,store,put_resource(resources,slot),events,commands,registrations,nextSystem,clock}
29	
30	# ApplyDeferred only drains structural commands. Machine commits require the
31	# separate marker; callers must not conflate the two public operations.
32	def structural_flush(~S: Data,~C: Type,~R: Type,~E: Data,world: W.World<S,C,R,E>) -> W.World<S,C,R,E>:
33	  W.barrier(~S,~C,~R,~E,world)