1	import Base
2	# Typed operational uses; capture has no synthetic schema resource identity.
3	type Target is Data:
4	  Component{key:String}
5	  Resource{key:String}
6	  Capture{}
7	type Mode is Data:Write{}
8	type Use is Data:Use{target:Target,mode:Mode}
9	type Description is Data:Description{uses:List<&2,Use>,opaque:Bool}
10	def none() -> Description:Description{[],True{}}
11	def known(uses:List<&2,Use>) -> Description:Description{uses,False{}}
12	def pair(left:Description,right:Description) -> Description:
13	  match left right:
14	    case Description{a,oa} Description{b,ob}:Description{List.append(&2,Use,a,b),Bool.or(oa,ob)}
15	def complete(value:Description) -> Bool:
16	  match value:
17	    case Description{_,opaque}:Bool.not(opaque)