21 lines
377 B
Dart
21 lines
377 B
Dart
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import 'dart:async';
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class AsyncLock {
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Future<void>? _lastOp;
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Future<T> run<T>(Future<T> Function() action) async {
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final previous = _lastOp;
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final completer = Completer<void>();
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_lastOp = completer.future;
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if (previous != null) {
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await previous;
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}
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try {
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return await action();
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} finally {
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completer.complete();
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}
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}
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}
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