gapt.proofs.lk.LKProof.scala Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of gapt_3 Show documentation

General Architecture for Proof Theory

The newest version!

package gapt.proofs.lk

import gapt.expr.formula.Formula
import gapt.proofs.Ant
import gapt.proofs.HOLSequent
import gapt.proofs.SequentIndex
import gapt.proofs.SequentProof
import gapt.proofs.Suc

import scala.collection.mutable

abstract class LKProof extends SequentProof[Formula, LKProof] {

  protected def LKRuleCreationException(message: String): LKRuleCreationException =
    new LKRuleCreationException(longName, message)

  /**
   * The end-sequent of the rule.
   */
  final def endSequent: HOLSequent = conclusion

  /**
   * Checks whether indices are in the right place and premise is defined at all of them.
   *
   * @param premise The sequent to be checked.
   * @param antecedentIndices Indices that should be in the antecedent.
   * @param succedentIndices Indices that should be in the succedent.
   */
  protected final def validateIndices(
      premise: HOLSequent,
      antecedentIndices: Seq[SequentIndex],
      succedentIndices: Seq[SequentIndex]
  ): Unit = {
    val antSet = mutable.HashSet[SequentIndex]()
    val sucSet = mutable.HashSet[SequentIndex]()

    for (i <- antecedentIndices) i match {
      case Ant(_) =>
        if (!premise.isDefinedAt(i))
          throw LKRuleCreationException(s"Sequent $premise is not defined at index $i.")

        if (antSet contains i)
          throw LKRuleCreationException(s"Duplicate index $i for sequent $premise.")

        antSet += i

      case Suc(_) => throw LKRuleCreationException(s"Index $i should be in the antecedent.")
    }

    for (i <- succedentIndices) i match {
      case Suc(_) =>
        if (!premise.isDefinedAt(i))
          throw LKRuleCreationException(s"Sequent $premise is not defined at index $i.")

        if (sucSet contains i)
          throw LKRuleCreationException(s"Duplicate index $i for sequent $premise.")

        sucSet += i

      case Ant(_) => throw LKRuleCreationException(s"Index $i should be in the succedent.")
    }
  }
}