Python 后期绑定问题

# test.py

def funs1():
    return (lambda x: x+i for i in range(4))

def funs2():
    return [lambda x: x+i for i in range(4)]

def funs3():
    return [(lambda x, i=i: x+i) for i in range(4)]

if __name__ == "__main__":
    print("fun1：")
    for f in funs1():
        print(f(0))
    print("fun2：")
    for f in funs2():
        print(f(0))
    print("fun3：")
    for f in funs3():
        print(f(0))

结果

# python3 test.py
fun1：
0
1
2
3
fun2：
3
3
3
3
fun3：
0
1
2
3