data class AmbiguousFunctions(val functions: List<FunctionCallResolver.FunctionResolutionAndBinding>) : ErrorReason
    data class ValReassignment(val localVal: LocalValue) : ErrorReason
    data class ExternalReassignment(val external: ObjectOrigin.External) : ErrorReason
    data class AssignmentTypeMismatch(val expected: DataType, val actual: DataType) : ErrorReason

    private
    fun mapPropertyErrors(errors: Iterable<ResolutionError>): List<PropertyNotAssignedReason> = errors.map {
        when (it.errorReason) {
            is ErrorReason.ExternalReassignment,
            ErrorReason.UnresolvedAssignmentLhs -> UnresolvedName

            is ErrorReason.UnresolvedReference -> UnresolvedName
            is ErrorReason.AssignmentTypeMismatch -> ValueTypeMismatch

                null
            }

            is AssignmentResolution.ReassignExternal -> {
                errorCollector.collect(ResolutionError(propertyAccess, ErrorReason.ExternalReassignment(firstMatch.external)))
                null
            }

            is AssignmentResolution.AssignProperty -> firstMatch.propertyReference
        }?.also {

        ErrorReason.DanglingPureExpression -> "dangling pure expression"
        is ErrorReason.DuplicateLocalValue -> "duplicate local 'val ${errorReason.name}'"
        is ErrorReason.ExternalReassignment -> "assignment to external property"
        ErrorReason.MissingConfigureLambda -> "a configuring block expected but not found"