override val rhs: ObjectOrigin
    ) : FailedToRecordAssignment

    data class Reassignment(
        val assignmentAdditionResult: AssignmentResolver.AssignmentAdditionResult.Reassignment,
        override val lhs: PropertyReferenceResolution,
        override val rhs: ObjectOrigin,
    ) : FailedToRecordAssignment

            data class DocumentCheckFailures(val failures: List<DocumentCheckFailure>) : StageFailure
            data class AssignmentErrors(val usages: List<AssignmentTraceElement.FailedToRecordAssignment>) : StageFailure
        }
    }
}


val <R : StepResult> EvaluationResult<R>.stepResultOrPartialResult
    get() = when (this) {
        is EvaluationResult.Evaluated -> stepResult

        }

        val assignmentTrace = assignmentTrace(resolution)
        val assignmentErrors = assignmentTrace.elements.filterIsInstance<AssignmentTraceElement.FailedToRecordAssignment>()
        if (assignmentErrors.isNotEmpty()) {
            failureReasons += AssignmentErrors(assignmentErrors)
        }

        is ErrorReason.NonReadableProperty -> "property cannot be used as a value: '${errorReason.property.name}'"
    }

    private
    fun describedUnassignedValueUsage(unassigned: AssignmentTraceElement.FailedToRecordAssignment): String {
        val errorMessage = when (unassigned) {
            is AssignmentTraceElement.Reassignment -> "Value reassigned"
            is AssignmentTraceElement.UnassignedValueUsed -> "Unassigned value used"