The package contains immutable value objects PositiveInt and PositiveDouble that encapsulate a positive number (any number greater than 0) which can be int or double. The value objects guarantee that their value is always positive and can't be changed after creation. They can't be created with 0 or a negative value.
dart pub add positive_num
Or specify the package's git url in pubspec.yaml at the dependencies section.
dependencies:
positive_num:
git:
url: https://github.com/maxeema/positive_num.git
Then import it in your code.
import 'package:positive_num/positive_num.dart';
import 'package:positive_num/positive_num.dart';
void main() {
var someNumber = 1;
//
final (:error, :instance) = PositiveInt.create(someNumber);
if (instance != null) {
final positiveInt = instance;
print('Created a PositiveInt, value: $positiveInt');
} else {
print('Error. $error');
}
}
dart pub get
dart run example/positive_num_example.dart
dart test
© Max Shemetov, 2023