终于找到bit 的资料了，我是poly 中看到的。

bit.and <integer1> <integer2>

Returns the <integer> result of AND-ing the bits in integer1 and integer2

bit.or <integer1> <integer2>

Returns the <integer> result of OR-ing the bits in integer1 and integer2

bit.xor <integer1> <integer2>

Returns the <integer> result of XOR-ing the bits in integer1 and integer2

bit.not <integer1>

Returns the <integer> result of flipping the bits in integer1