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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, Exception, OSError],
tags: [RootEffect, ReadEnvEffect, ReadIOEffect, ReadDirEffect], forbids: [].}-
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