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New "strict funcs" checking. Much simpler and hopefully easier to teach than the old but more advanced algorithm that can/could be found in varpartitions.nim.
proc isDangerousLocation(n: PNode; owner: PSym): bool {.
...raises: [KeyError, ValueError, IOError, OSError, Exception], tags: [
WriteIOEffect, ReadEnvEffect, ReadIOEffect, ReadDirEffect, RootEffect],
forbids: [].}-
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