Coverage Summary for Class: TermLookup (it.unibo.tuprolog.argumentation.core.model.mining)

 package it.unibo.tuprolog.argumentation.core.model.mining
 
 import it.unibo.tuprolog.core.Term
 import it.unibo.tuprolog.unify.Unificator
 
 /**
  * The items, looked up by the term of each ([key]). Mined terms are matched through unification, which amounts to
  * structural equality when both sides are ground: in that case a hash lookup replaces the scan of all the candidates
  * for every attack, support and label.
  */
 internal class TermLookup<T>(
     items: List<T>,
     key: (T) -> Term,
 ) {
     private val entries = items.map { key(it) to it }
 
     private val index: Map<Term, T>? =
         if (entries.all { it.first.isGround }) {
             mutableMapOf<Term, T>().also { map -> entries.forEach { (term, item) -> map.getOrPut(term) { item } } }
         } else {
             null
         }
 
     /** The first item whose term matches [term] */
     fun firstOrNull(term: Term): T? =
         if (index != null && term.isGround) {
             index[term]
         } else {
             entries.firstOrNull { Unificator.default.match(it.first, term) }?.second
         }
 }