"""

is和 ==的区别

"""

a = 'abc'

b = 'abc'

print("都是字符串-a is b--", a is b)

print("都是字符串-a == b--", a == b)

c = 11

d = 11

print("都是数字-c is d--", c is d)

print("都是数字-c == d--", c == d)

e = [0, 1, 2]

f = [0, 1, 2]

print("都是列表-e is f--", e is f)

print("都是列表-e == f--", e == f)

g = h = [0, 1, 2]

print("都是列表-g is f--", g is h)

print("都是列表-g == f--", g == h)

i = (0, 1, 2)

j = (0, 1, 2)

print("都是元祖-i is j--", i is j)

print("都是元祖-i == j--", i == j)

k = {"name": "张三"}

m = {"name": "张三"}

print("都是字典-k is m--", k is m)

print("都是字典-k == m--", k == m)

print("a的id--", id(a))

print("b的id--", id(b))

print("c的id--", id(c))

print("d的id--", id(d))

print("e的id--", id(e))

print("f的id--", id(f))

print("g的id--", id(g))

print("h的id--", id(h))

print("i的id--", id(i))

print("j的id--", id(j))

print("k的id--", id(k))

print("m的id--", id(m))

输出结果:

image.png

总结：is是判断id是否相等，==是判断数据是否相等，如果两个变量的值是字符串，数字，元祖，那么is和==的结果无区别。如果是列表和字典，is是false，==是true，特例 g = h = [0, 1, 2]这样的列表，is也是true，因为指向同一空间地址