Coverage Summary for Class: Subtract (it.unibo.tuprolog.argumentation.core.primitives.utils)

 package it.unibo.tuprolog.argumentation.core.primitives.utils
 
 import it.unibo.tuprolog.core.List
 import it.unibo.tuprolog.core.Substitution
 import it.unibo.tuprolog.core.Term
 import it.unibo.tuprolog.solve.ExecutionContext
 import it.unibo.tuprolog.solve.primitive.Solve
 import it.unibo.tuprolog.solve.primitive.TernaryRelation
 
 /**
  * subtract(+List, +Removed, ?Rest): the elements of List not in Removed, in order (elements compared as ground terms),
  * without the recursion of a Prolog subtract (whose frames would all keep the rest of the list)
  */
 internal object Subtract : TernaryRelation.WithoutSideEffects<ExecutionContext>("subtract") {
     override fun Solve.Request<ExecutionContext>.computeAllSubstitutions(
         first: Term,
         second: Term,
         third: Term,
     ): Sequence<Substitution> {
         if (first !is List || second !is List) return emptySequence()
         val removed = second.toList().toSet()
         return unifyWith(third, List.of(first.toList().filter { it !in removed }))
     }
 }