在流上使用时,Distinct() 似乎不会过滤掉相同的结果

Fra*_*cca 5 asynchronous iterable stream dart flutter

请看一下这段代码=>

void main() async {
  Stream<int> _intStream() async* {
    for (int i = 0; i < 10; i++) yield i;
  }

  Stream<int> _even() => _intStream().where((int i) => i % 2 == 0);
  Stream<bool> _isEven(Stream<int> stream) => stream.map((int i) => i % 2 == 0);

  print('test 1: should print 5 [true] and 5 [false] alternate');
  await for (bool b in _isEven(_intStream())) {
    print('test 1: $b');
  }

  print('test 2: should print 5 [true]');
  await for (bool b in _isEven(_even())) {
    print('test 2: $b');
  }

  print('test 3: should print ONLY ONE [true]');
  await for (bool b in _isEven(_even().distinct())) {
    print('test 3: $b');
  }
}
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我使用distinct()错误的方式吗?

先感谢您

Fra*_*cca 2

没关系,我只是把不同的放在错误的地方,以下按预期工作

void main() async {
  Stream<int> _intStream() async* {
    for (int i = 0; i < 10; i++) yield i;
  }

  Stream<int> _even() => _intStream().where((int i) => i % 2 == 0);
  Stream<bool> _isEven(Stream<int> stream) => stream.map((int i) => i % 2 == 0);

  print('test 1: should print 5 [true] and 5 [false] alternate');
  await for (bool b in _isEven(_intStream())) {
    print('test 1: $b');
  }

  print('test 2: should print 5 [true]');
  await for (bool b in _isEven(_even())) {
    print('test 2: $b');
  }

  print('test 3: should print ONLY ONE [true]');
  await for (bool b in _isEven(_even()).distinct()) {
    print('test 3: $b');
  }
}
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