AnyBSONValue should conform to Hashable

private func _hash(into hasher: inout Hasher, bsonValue: BSONValue?) {

    switch (bsonValue) {

    case (let value as Int):

        hasher.combine(value)

    case (let value as Int32):

        hasher.combine(value)

    case (let value as Int64):

        hasher.combine(value)

    case (let value as Double):

        hasher.combine(value)

    case (let value as Decimal128):

        hasher.combine(value.data)

    case (let value as Bool):

        hasher.combine(value)

    case (let value as String):

        hasher.combine(value)

    case (let value as RegularExpression):

        hasher.combine(value.options)

        hasher.combine(value.pattern)

    case (let value as Timestamp):

        hasher.combine(value.timestamp)

    case (let value as Date):

        hasher.combine(value.timeIntervalSince1970)

    case (_ as MinKey):

        hasher.combine(1)

    case (_ as MaxKey):

        hasher.combine(1)

    case (let value as ObjectId):

        hasher.combine(value.description)

    case (let value as CodeWithScope):

        hasher.combine(value.code)

        _hash(into: &hasher, bsonValue: value.scope)

    case (let value as Binary):

        hasher.combine(value.data)

    case (let value as Document):

        hasher.combine(value.canonicalExtendedJSON)

    case (let value as [BSONValue?]): // TODO: SWIFT-242

        return value.forEach { _hash(into: &hasher, bsonValue: $0!) }

    default: break

    }

}

extension BSONValue {

    func hash(into hasher: inout Hasher) {

        _hash(into: &hasher, bsonValue: self)

    }

}