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

 package it.unibo.tuprolog.argumentation.core.primitives.utils
 
 import it.unibo.tuprolog.argumentation.core.runtime.Arg2pUnificator
 import it.unibo.tuprolog.core.List
 import it.unibo.tuprolog.core.Term
 import it.unibo.tuprolog.solve.ExecutionContext
 import it.unibo.tuprolog.solve.Signature
 import it.unibo.tuprolog.solve.exception.error.TypeError
 import it.unibo.tuprolog.solve.primitive.Primitive
 import it.unibo.tuprolog.solve.primitive.Solve
 
 /** appendLists(Lists, Result): Result is the concatenation of the lists in Lists */
 internal object AppendLists : Primitive {
     val signature: Signature = Signature("appendLists", 2)
 
     override fun solve(request: Solve.Request<ExecutionContext>): Sequence<Solve.Response> {
         val lists: Term = request.arguments[0]
 
         if (lists !is List) {
             throw TypeError.forGoal(
                 request.context,
                 request.signature,
                 TypeError.Expected.LIST,
                 lists,
             )
         }
 
         val items =
             lists.toList().flatMap { list ->
                 if (list !is List) {
                     throw TypeError.forGoal(
                         request.context,
                         request.signature,
                         TypeError.Expected.LIST,
                         list,
                     )
                 }
                 list.toList()
             }
         val unifier = Arg2pUnificator.mgu(request.arguments[1], List.of(items))
         return sequenceOf(if (unifier.isSuccess) request.replyWith(unifier) else request.replyFail())
     }
 }