027_sets.dart

// ignore_for_file: unused_local_variable

void foo17() {
// Create an empty set of strings.
  var ingredients = <String>{};

// Add new items to it.
  ingredients.addAll(['gold', 'titanium', 'xenon']);
  assert(ingredients.length == 3);

// Adding a duplicate item has no effect.
  ingredients.add('gold');
  assert(ingredients.length == 3);

// Remove an item from a set.
  ingredients.remove('gold');
  assert(ingredients.length == 2);

// You can also create sets using
// one of the constructors.
  var atomicNumbers = Set.from([79, 22, 54]);
}

void foo18() {
  var ingredients = Set<String>();
  ingredients.addAll(['gold', 'titanium', 'xenon']);

// Check whether an item is in the set.
  assert(ingredients.contains('titanium'));

// Check whether all the items are in the set.
  assert(ingredients.containsAll(['titanium', 'xenon']));
}

void foo19() {
  var ingredients = Set<String>();
  ingredients.addAll(['gold', 'titanium', 'xenon']);

// Create the intersection of two sets.
  var nobleGases = Set.from(['xenon', 'argon']);
  var intersection = ingredients.intersection(nobleGases);
  assert(intersection.length == 1);
  assert(intersection.contains('xenon'));
}