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3188 :: Nimscript: setLen segfaults?

• Udiknedormin (orginal) [2017-09-22T21:47:29+02:00] view original

  When I used keepItIf in a nimble scirpt, it segfaulted. After copy-pasting the templates body and trying to play with it a little bit it turned out setLen was the one to blame. If I replace moving the elements to adding them to another seq and then assign it to the original one, everything works fine. Does anyone know why is that so or how can I prevent it from segfaulting?

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• Tiberium (orginal) [2017-09-22T21:57:41+02:00] view original

  Udiknedormin: can you post a code example? And also create an issue on github

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• Udiknedormin (orginal) [2017-09-22T23:49:38+02:00] view original

  task tests, "run tests":
    --hints: off
    --linedir: on
    --stacktrace: on
    --linetrace: on
    --debuginfo
    --path: "."
    --run
    var dir_list = listDirs("tests")
    dir_list.keepItIf(it != "tests/nimcache")
  # segfaults
  Run

  task tests, "run tests":
    --hints: off
    --linedir: on
    --stacktrace: on
    --linetrace: on
    --debuginfo
    --path: "."
    --run
    var dir_list = @["tests/nimcache"]  # and other subdirs
    dir_list.keepItIf(it != "tests/nimcache")
  # works fine
  Run

  task tests, "run tests":
    --hints: off
    --linedir: on
    --stacktrace: on
    --linetrace: on
    --debuginfo
    --path: "."
    --run
    var dir_list = newSeq[string]()
    for dir in listDirs("tests"):
      if dir != "tests/nimcache":
        dir_list.add(dir)
  # also works
  Run

  I wasn't sure if it was a bug or I don't get how NimScript does things so I didn't want to create a bug issue yet.

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• cdome (orginal) [2017-09-23T01:13:05+02:00] view original

  seq can be nil, you need to check for that sometimes. KeepitIf will segfault if you will pass nil.

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• Udiknedormin (orginal) [2017-09-24T23:47:23+02:00] view original

  @cdome It wasn't a nil in this case.

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