bat/tests/syntax-tests/source/Dart/test.dart
2020-10-05 18:53:35 +02:00

134 lines
2.9 KiB
Dart

/* array sorting alogorithm */
int partition(List list, int low, int high) {
if (list == null || list.length == 0) return 0;
int pivot = list[high];
int i = low - 1;
void swap(List list, int i, int j) {
int temp = list[i];
list[i] = list[j];
list[j] = temp;
}
for (int j = low; j < high; j++) {
if (list[j] <= pivot) {
i++;
swap(list, i, j);
}
swap(list, i + 1, high);
return i + 1;
}
}
void quickSort(List list, int low, int high) {
if (low < high) {
int pi = partition(list, low, high);
quickSort(list, low, pi - 1);
quickSort(list, pi + 1, high);
}
}
void merge(List list, int leftIndex, int middleIndex, int rightIndex) {
int leftSize = middleIndex - leftIndex + 1;
int rightSize = rightIndex - middleIndex;
List leftList = new List(leftSize);
List rightList = new List(rightSize);
for (int i = 0; i < leftSize; i++) leftList[i] = list[leftIndex + i];
for (int j = 0; j < rightSize; j++) rightList[j] = list[middleIndex + j + 1];
int i = 0, j = 0;
int k = leftIndex;
while (i < leftSize && j < rightSize) {
if (leftList[i] <= rightList[j]) {
list[k] = leftList[i];
i++;
} else {
list[k] = rightList[j];
j++;
}
k++;
}
while (i < leftSize) {
list[k] = leftList[i];
i++;
k++;
}
while (j < rightSize) {
list[k] = rightList[j];
j++;
k++;
}
}
void mergeSort(List list, int leftIndex, int rightIndex) {
if (leftIndex < rightIndex) {
int middleIndex = (rightIndex + leftIndex) ~/ 2;
mergeSort(list, leftIndex, middleIndex);
mergeSort(list, middleIndex + 1, rightIndex);
merge(list, leftIndex, middleIndex, rightIndex);
}
}
/* variables */
var name = 'Voyager I';
var year = 1977;
var antennaDiameter = 3.7;
var flybyObjects = ['Jupiter', 'Saturn', 'Uranus', 'Neptune'];
var image = {
'tags': ['saturn'],
'url': '//path/to/saturn.jpg'
};
/*classes */
class Spacecraft {
String name;
DateTime launchDate;
Spacecraft(this.name, this.launchDate) {}
// Named constructor that forwards to the default one.
Spacecraft.unlaunched(String name) : this(name, null);
int get launchYear => launchDate?.year;
void describe() {
print('Spacecraft: $name');
if (launchDate != null) {
int years = DateTime.now().difference(launchDate).inDays ~/ 365;
print('Launched: $launchYear ($years years ago)');
} else {
print('Unlaunched');
}
}
}
/* Mixins */
class PilotedCraft extends Spacecraft with Piloted {
// ···
}
/* Interfaces and abstract classes */
class MockSpaceship implements Spacecraft {
// ···
}
/* async */
Future<void> printWithDelay(String message) {
return Future.delayed(const Duration(seconds: 2)).then((_) {
print(message);
});
}
Stream<String> report(Spacecraft craft, Iterable<String> objects) async* {
for (var object in objects) {
await Future.delayed(const Duration(seconds: 2));
yield '${craft.name} flies by $object';
}
}