)]}'
{
  "commit": "8d3b6ce54ccb09dd970cd45fc3cded4a35beac31",
  "tree": "c2c51402da8f3af22f8e4018b92bb7e0ad265f4e",
  "parents": [
    "882e883be2fa3fca0cf75fd3dc011237d91663ed"
  ],
  "author": {
    "name": "Konstantin Shcheglov",
    "email": "scheglov@google.com",
    "time": "Mon Jan 08 18:55:48 2024 +0000"
  },
  "committer": {
    "name": "Commit Queue",
    "email": "dart-scoped@luci-project-accounts.iam.gserviceaccount.com",
    "time": "Mon Jan 08 18:55:48 2024 +0000"
  },
  "message": "Use flattenedToList/flattenedToSet instead of generic expand().\n\nIt is faster.\n\n[expand: 102]\n[flattened: 131]\n[flattened2: 37]\n\nimport \u0027package:collection/collection.dart\u0027;\n\nmain() {\n  const outerLength \u003d 100;\n  const innerLength \u003d 10;\n  final listOfLists \u003d List.generate(outerLength, (i) {\n    return List.generate(innerLength, (j) \u003d\u003e i * innerLength + j);\n  });\n\n  for (var i \u003d 0; i \u003c 10; i++) {\n    f(listOfLists);\n  }\n}\n\nvoid f(List\u003cList\u003cint\u003e\u003e listOfLists) {\n  const repeatCount \u003d 10000;\n\n  {\n    final timer \u003d Stopwatch()..start();\n    for (var i \u003d 0; i \u003c repeatCount; i++) {\n      listOfLists.expand((e) \u003d\u003e e).toList();\n    }\n    print(\u0027[expand: ${timer.elapsedMilliseconds}]\u0027);\n  }\n\n  {\n    final timer \u003d Stopwatch()..start();\n    for (var i \u003d 0; i \u003c repeatCount; i++) {\n      listOfLists.flattened.toList();\n    }\n    print(\u0027[flattened: ${timer.elapsedMilliseconds}]\u0027);\n  }\n\n  {\n    final timer \u003d Stopwatch()..start();\n    for (var i \u003d 0; i \u003c repeatCount; i++) {\n      listOfLists.flattened2.toList();\n    }\n    print(\u0027[flattened2: ${timer.elapsedMilliseconds}]\u0027);\n  }\n}\n\nextension ListListExtensions\u003cT\u003e on List\u003cList\u003cT\u003e\u003e {\n  Iterable\u003cT\u003e get flattened2 {\n    return [\n      for (final elements in this) ...elements,\n    ];\n  }\n}\n\nChange-Id: I0bf9dc0c8735fe62aab69cbce276254e2db110f9\nReviewed-on: https://dart-review.googlesource.com/c/sdk/+/345202\nReviewed-by: Jacob Richman \u003cjacobr@google.com\u003e\nReviewed-by: Brian Wilkerson \u003cbrianwilkerson@google.com\u003e\nReviewed-by: Phil Quitslund \u003cpquitslund@google.com\u003e\nCommit-Queue: Konstantin Shcheglov \u003cscheglov@google.com\u003e\n",
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