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Resolution-agnostic API for logic solvers

There is a newer version: 1.0.4

package it.unibo.tuprolog.solve.stdlib.primitive

import it.unibo.tuprolog.core.Struct
import it.unibo.tuprolog.core.Term
import it.unibo.tuprolog.solve.ExecutionContext
import it.unibo.tuprolog.solve.Solution
import it.unibo.tuprolog.solve.primitive.Solve
import it.unibo.tuprolog.solve.primitive.TernaryRelation
import it.unibo.tuprolog.unify.Unificator.Companion.mguWith
import it.unibo.tuprolog.core.List as LogicList

object FindAll : TernaryRelation.NonBacktrackable("findall") {
    override fun Solve.Request.computeOne(first: Term, second: Term, third: Term): Solve.Response {
        ensuringArgumentIsInstantiated(1)
        ensuringArgumentIsCallable(1)
        val solutions = solve(second as Struct).toList()
        val error = solutions.asSequence().filterIsInstance().firstOrNull()
        if (error != null) {
            return replyException(error.exception.pushContext(context))
        }
        val mapped = solutions.asSequence()
            .filterIsInstance()
            .map { first[it.substitution].freshCopy() }
        return replyWith(third mguWith LogicList.from(mapped))
    }
}