Coverage Summary for Class: Goal (it.unibo.tuprolog.argumentation.parallel.node)

 package it.unibo.tuprolog.argumentation.parallel.node
 
 import it.unibo.tuprolog.argumentation.Arg2pException
 import it.unibo.tuprolog.argumentation.core.model.terms.ArgumentTerm
 import it.unibo.tuprolog.core.Atom
 import it.unibo.tuprolog.core.Struct
 import it.unibo.tuprolog.core.Substitution
 import it.unibo.tuprolog.core.Term
 import it.unibo.tuprolog.core.operators.OperatorSet
 import it.unibo.tuprolog.core.parsing.parse
 import it.unibo.tuprolog.solve.Solution
 import it.unibo.tuprolog.solve.Solver
 import it.unibo.tuprolog.unify.Unificator
 
 /**
  * A goal parsed once, its variables bound to terms each time it is solved: the arguments are passed as terms, never
  * written in the text of a goal (a goal carrying much data makes every step of its resolution slower, and its text
  * would be parsed each time)
  */
 internal class Goal(
     text: String,
     operators: OperatorSet,
 ) {
     private val template = Struct.parse(text, operators)
     private val variables = template.variables.associateBy { it.name }
 
     /** The goal with the variables named in [bindings] bound */
     fun with(vararg bindings: Pair<String, Term>): Struct =
         template.apply(Substitution.of(bindings.associate { (name, term) -> variables.getValue(name) to term })).castToStruct()
 
     /**
      * The values of the variables of the goal, by name, in each solution [solver] gives it with [bindings]: those of the
      * goal alone, whatever the variables of the terms bound are named
      */
     fun solutions(
         solver: Solver,
         vararg bindings: Pair<String, Term>,
     ): List<Map<String, Term>> {
         val bound = bindings.map { it.first }.toSet()
         return solver
             .solve(with(*bindings))
             .filter { it is Solution.Yes }
             .map { solution ->
                 variables
                     .filterKeys { it !in bound }
                     .mapNotNull { (name, variable) -> solution.substitution[variable]?.let { name to it } }
                     .toMap()
             }.toList()
     }
 }
 
 /** The values of the variables of [goal], Prolog text, by name, in each of its solutions */
 internal fun Solver.solutions(goal: String): List<Map<String, Term>> = Goal(goal, operators).solutions(this)
 
 /** The first solution of [goal], Prolog text */
 internal fun Solver.solveOnce(goal: String): Solution = solve(Struct.parse(goal, operators)).first()
 
 /** Whether [goal], Prolog text, succeeds */
 internal fun Solver.holds(goal: String): Boolean = solveOnce(goal).isYes
 
 /** [solution], unless it is a halt: its error raised, as an [Arg2pException] */
 internal fun checked(solution: Solution): Solution {
     if (solution.isHalt) {
         val error = solution.exception
         throw Arg2pException(error?.message ?: error?.toString() ?: solution.toString())
     }
     return solution
 }
 
 /** Whether exploring [general] explores [specific] as well: [specific], its variables fixed, is an instance of it */
 internal fun covers(
     general: Term,
     specific: Term,
 ): Boolean {
     val fixed = specific.variables.distinct().mapIndexed { i, variable -> variable to Atom.of("fixed variable $i") }
     return Unificator.default.match(general, specific.apply(Substitution.of(fixed.toMap())))
 }
 
 /** The statement [argument], the term of an argument, concludes */
 internal fun claimOf(argument: Term): Term = ArgumentTerm.parts(argument)!!.claim!!