Python：while循环的条件不会以递归函数终止

Question

我正在尝试实现基本的递归函数，一旦高参数不大于低参数，该函数便应终止。

import time
def whileBlock(low, high):
    print("New low value:",low,"------","New high value:",high)
    while low < high:
        mid = (low + high)//2
        print("Low:",low,"Mid:",mid,"high:",high)
        time.sleep(2)

        whileBlock(low, mid)

whileBlock(0,10) 

计算出的中间值被传递给递归函数。 对于前4个迭代，代码按预期运行。从第5次迭代开始，尽管high等于0（与low相同），但是条件没有终止并且陷入无限循环。

当条件上方的print语句显示为0时，为什么while循环仍然变得高至1，我无法理解。

代码输出

whileBlock(0,10)
New low value: 0 ------ New high value: 10
Low: 0 Mid: 5 high: 10
New low value: 0 ------ New high value: 5
Low: 0 Mid: 2 high: 5
New low value: 0 ------ New high value: 2
Low: 0 Mid: 1 high: 2
New low value: 0 ------ New high value: 1
Low: 0 Mid: 0 high: 1
New low value: 0 ------ New high value: 0
Low: 0 Mid: 0 high: 1
New low value: 0 ------ New high value: 0
Low: 0 Mid: 0 high: 1
New low value: 0 ------ New high value: 0
Low: 0 Mid: 0 high: 1
New low value: 0 ------ New high value: 0
Low: 0 Mid: 0 high: 1