proc hashTree(n: PNode): Hash {....raises: [Exception, OSError, KeyError,
    ValueError, IOError], tags: [RootEffect, WriteIOEffect, ReadEnvEffect,
                                 ReadIOEffect, ReadDirEffect], forbids: [].}

proc nodeTableGet(t: TNodeTable; key: PNode): int {.
    ...raises: [Exception, OSError, KeyError, ValueError, IOError], tags: [
    RootEffect, WriteIOEffect, ReadEnvEffect, ReadIOEffect, ReadDirEffect],
    forbids: [].}

proc nodeTablePut(t: var TNodeTable; key: PNode; val: int) {.
    ...raises: [Exception, OSError, KeyError, ValueError, IOError], tags: [
    RootEffect, WriteIOEffect, ReadEnvEffect, ReadIOEffect, ReadDirEffect],
    forbids: [].}

proc nodeTableTestOrSet(t: var TNodeTable; key: PNode; val: int): int {.
    ...raises: [Exception, OSError, KeyError, ValueError, IOError], tags: [
    RootEffect, WriteIOEffect, ReadEnvEffect, ReadIOEffect, ReadDirEffect],
    forbids: [].}