The Generics type `Function(T a)` is only allowed one paramter now. Not sure how to improve the type yet.


## Usage

`$ dart ./main.dart`

```
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```

main.dart

```dart
import 'dart:async';
import './throttle.dart';


void main() async {
  var f = Throttle.create((int n) {
    print(n);
  }, duration: const Duration(milliseconds: 1000));

  for (int i = 0; i < 10; i++) {
    f(i);
    await Future.delayed(Duration(milliseconds: 500));
  }
}

```


## throttle.dart


```dart
import 'dart:async';

typedef ThrottledFunction<T> = Function(T a);

class Throttle<T> {
  Duration duration;
  Timer? _timer;
  ThrottledFunction<T>? _throttledFunction;

  Throttle(this._throttledFunction,
      {this.duration = const Duration(milliseconds: 500)});

  void call(T a) {
    if (_timer == null || !_timer!.isActive) {
      _timer = Timer(duration, () {
        _throttledFunction!(a);
        _timer = null;
      });
    }
  }

  static Throttle<T> create<T>(ThrottledFunction<T> function,
      {duration = const Duration(milliseconds: 500)}) {
    return Throttle(function, duration: duration);
  }
}
```