{
  "$type": "site.standard.document",
  "bskyPostRef": {
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    "uri": "at://did:plc:pi6woz4d47bkuws673w2il2r/app.bsky.feed.post/3mgnrcuzcbgu2"
  },
  "path": "/t/ann-type-safe-diffutctime/13778#post_4",
  "publishedAt": "2026-03-09T14:08:19.000Z",
  "site": "https://discourse.haskell.org",
  "tags": [
    "unsafeIOToSTM",
    "github.com/yaitskov/a-piece-of-flake",
    "src/PieceOfFlake/Flake/Repo.hs",
    "`16f035a74`"
  ],
  "textContent": "BurningWitness:\n\n> Have you read the documentation to unsafeIOToSTM?\n\nYes, I do. getCurrentTime doesn’t modify anything.\nOtherwise I need to break STM transaction to get time.\nGitHub has bug tracker.\n\nBurningWitness:\n\n> Not clear when this situation might arise, please elaborate.\n\ngithub.com/yaitskov/a-piece-of-flake\n\n#### src/PieceOfFlake/Flake/Repo.hs\n\n`16f035a74`\n\n\n\n\n\n\n        96.     (\\(fu, Tagged ifq) -> do\n\n\n        97.        addTimeDif fr.repoStats.meanTimeInFetchQueue ifq\n\n\n        98.        pure fu)\n\n\n        99.\n\n        100. data TimeInFetchQueue\n\n\n        101.\n\n        102. popFlakeSubmitionStm  ::\n\n\n        103.   FetcherId ->\n\n\n        104.   FlakeRepo ->\n\n\n        105.   WriterLoggingT STM (Maybe (FlakeUrl, Tagged TimeInFetchQueue NominalDiffTime))\n\n\n        106. popFlakeSubmitionStm ftid fr = do\n\n\n        107.   fSub <- lift $ readTQueue fr.fetcherQueue\n\n\n        108.   lift $ modifyTVar' fr.fetcherQueueLen (\\x -> x - 1)\n\n\n        109.   fql <- lift $ readTVar fr.fetcherQueueLen\n\n\n        110.   $(logInfo) $ \"Fetcher queue decreased to \" <> P.show fql\n\n\n        111.   case fSub of\n\n\n        112.     Nothing -> pure Nothing\n\n\n        113.     Just fu ->\n\n\n        114.       lift (lookup fu fr.flakes) >>= \\case\n\n\n        115.         Just (SubmittedFlake { flakeUrl, submittedAt })\n\n\n        116.           | flakeUrl == fu -> do\n\n\n\n",
  "title": "[ANN] type safe diffUTCTime"
}