hugovdm

class A {
  const A(this.x) : assert(x != null);
  final String x;
  String toString() => 'A: $x';
}

main() {
  // Why does this not cause an assertion failure?
  A a = A(null);
  print(a);

hugovdm

class Idx {
  Idx(this.val);
  int val;
}

class S {
  final List<int> _list = <int>[];
  add(int value) => _list.add(value);
  remove(int index) => _list.removeAt(index);

hugovdm

class MyImmutable {
  final String _x;
  const MyImmutable([String x])
      : _x = (x != null) ? x.length > 0 ? x : null : null;
  String toString() => 'MyImmutable("$_x")';
}

void main() {
  // These work:
  print(const MyImmutable('a'));

hugovdm

String fmtCompares(double a, double b) {
  return '${a < b}, ${a == b}, ${a > b}, ${a.compareTo(b)}';
}

void main() {
  double nan = 0 / 0;
  double negZero = -0.0;
  var l = [-1.0, 0.0, 1.0, nan, negZero];
  print(l);
  l.sort();

hugovdm

main() {
  print(
      "code units are 2 bytes in UTF-16. In some cases, one needs a surrogate pair of code units to form a code point. And one might need multiple code points, multiple characters, to form a single grapheme (e.g. an emoji).");

  print('');

  var clapping = '\u{1f44f}';
  print(clapping);
  print("codeUnits: ${clapping.codeUnits}.");
  print("runes, providing code points, not code units: ${clapping.runes}.");