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8130029374
* Use persistent hash map to store _inheritedWidgets Instead of using a HashMap and copying it down the tree which leads to quadratic time and space complexity use a persistent data structure which can amortize the cost by sharing parts of the structure. The data shows HAMT based PersistentHashMap to be 5-10x faster for building _inheritedWidgets and considerably more space effecient (e.g. bringing amount of memory allocated when constructing _inheritedWidgets in a tree with 150 InheritedWidget down to 70Kb from 970Kb). PersistentHashMap is slower than HashMap for access: 2-3x in relative terms, but in absolute terms we are only talking about ~0.2ns slow down per access and various app benchmarks we run have have not revealed any significant regressions.
47 lines
1.5 KiB
Dart
47 lines
1.5 KiB
Dart
// Copyright 2014 The Flutter Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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/// Core Flutter framework primitives.
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///
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/// The features defined in this library are the lowest-level utility
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/// classes and functions used by all the other layers of the Flutter
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/// framework.
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library foundation;
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export 'package:meta/meta.dart' show
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factory,
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immutable,
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mustCallSuper,
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nonVirtual,
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optionalTypeArgs,
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protected,
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required,
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visibleForTesting;
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export 'src/foundation/annotations.dart';
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export 'src/foundation/assertions.dart';
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export 'src/foundation/basic_types.dart';
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export 'src/foundation/binding.dart';
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export 'src/foundation/bitfield.dart';
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export 'src/foundation/change_notifier.dart';
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export 'src/foundation/collections.dart';
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export 'src/foundation/consolidate_response.dart';
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export 'src/foundation/constants.dart';
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export 'src/foundation/debug.dart';
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export 'src/foundation/diagnostics.dart';
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export 'src/foundation/isolates.dart';
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export 'src/foundation/key.dart';
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export 'src/foundation/licenses.dart';
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export 'src/foundation/math.dart';
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export 'src/foundation/node.dart';
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export 'src/foundation/object.dart';
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export 'src/foundation/observer_list.dart';
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export 'src/foundation/persistent_hash_map.dart';
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export 'src/foundation/platform.dart';
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export 'src/foundation/print.dart';
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export 'src/foundation/serialization.dart';
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export 'src/foundation/stack_frame.dart';
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export 'src/foundation/synchronous_future.dart';
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export 'src/foundation/unicode.dart';
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