minted_geography 1.1.0
minted_geography: ^1.1.0 copied to clipboard
Well-modelled Dart value types for geography: GeoCoordinate (ISO 6709 in all three field widths) and Geohash (base32 cells that decode). Part of the minted family.
example/minted_geography_example.dart
// This example prints to stdout so it runs standalone via `dart run`.
// ignore_for_file: avoid_print
import 'package:minted/minted.dart';
import 'package:minted_geography/minted_geography.dart';
void main() {
// `GeoCoordinate` names the pair, because a swapped latitude and longitude is a type bug no range
// check catches. ISO 6709 picks the unit by field width, and all three widths fold to degrees.
// #region geo
final eiffelTower = GeoCoordinate.tryParse('+48.8577+002.295/')!;
print(eiffelTower.latitude); // 48.8577
print(eiffelTower.iso6709); // +48.8577+002.295/ (canonical form)
print(eiffelTower.sexagesimal); // 48°51′27.72″N 2°17′42″E (display form)
print(GeoCoordinate.tryParse('+5012-00010/')?.latitude); // 50.2 (degrees and minutes)
print(GeoCoordinate.tryParse('+46+2/')); // null (an unpadded longitude is a different location)
// #endregion
// `Geohash` names a cell, not a point, so the round trip through one coordinate is not identity.
// #region geohash
final cell = Geohash.from(coordinate: eiffelTower, precision: NaturalNumber.tryFrom(5)!);
print(cell.value); // u09tu (canonical form: trimmed, lower-cased)
print(cell.centre.iso6709); // +48.84521484375+002.30712890625/ (the cell centre, not the tower)
print(Geohash.from(coordinate: cell.centre, precision: NaturalNumber.tryFrom(5)!)); // u09tu
print(Geohash.tryParse('ezsa2')); // null ('a' is not in the geohash alphabet)
// #endregion
}