Python - 解包的各种骚操作

a, b, c = [1, 2, 3]

print(a, b, c)


# 输出结果
1 2 3 

a, b = [1, 2, 3]


# 输出结果
    a, b = [1, 2, 3]
ValueError: too many values to unpack (expected 2)

>>> a,b,c = (1,2,3)
>>> a
1
>>> b
2
>>> c
3

>>> a,b,c = "abc"
>>> a
‘a‘
>>> b
‘b‘
>>> c
‘c‘

>>> a,b,c = {1,2,3}
>>> a
1
>>> b
2
>>> c
3

>>> a,b,c = {"a":1, "b":2, "c":3}
>>> a
‘a‘
>>> b
‘b‘
>>> c
‘c‘

>>> a, b = 1, 2
>>> a
1
>>> b
2

# 生成器
a, b, c = (x + 1 for x in range(3))
print(a, b, c)


# 输出结果
1 2 3 

a, b = [1, 2, 3]


# 输出结果
    a, b = [1, 2, 3]
ValueError: too many values to unpack (expected 2)

# 多变量
a, b, *c = [1, 2, 3, 4, 5]
print(a, b, c)


# 输出结果
1 2 [3, 4, 5]

# 多变量
a, b, *c, d = [1, 2, 3, 4, 5]
print(a, b, c, d)


# 输出结果
1 2 [3, 4] 5

# 函数
def test(a, b, c):
    print(a, b, c)


# 正常逐个传参
test(1, 2, 3)

# 只传一个可迭代对象，就需要解包
test(*[1, 2, 3])
test(*{1, 2, 3})
test(*(1, 2, 3))


# 输出结果
1 2 3
1 2 3
1 2 3
1 2 3

# 函数
def test(a, b, c):
    print(a, b, c)


# 关键字传参
test(a=1, b=2, c=3)

# 只传一个可迭代对象，就需要解包，和上面写法是等价的
test(**{"a": 1, "b": 2, "c": 3})


# 输出结果
1 2 3
1 2 3

# 函数
def test(a, b, c, d, e, f):
    print(a, b, c, d, e, f)


test(*[1, 2, ], *[3, 4, ], **{"e": 5}, **{"f": 6})


# 输出结果
1 2 3 4 5 6

# 表达式解包
print(range(3), 3)
print(*range(3), 3)

print([*range(3), 3])

print({"a": 1, **{"b": 2, "c": 3}})


# 输出结果
range(0, 3) 3
0 1 2 3
[0, 1, 2, 3]
{‘a‘: 1, ‘b‘: 2, ‘c‘: 3}

# 解包拼接列表
list1 = [1, 2]
list2 = range(3, 5)
list3 = [*list1, *list2]
print(list3)


# 输出结果
[1, 2, 3, 4]

# 解包拼接字典
dict1 = {"a": 1, "b": 2}
dict2 = {"name": "yy", "age": 22}
dict3 = {**dict1, **dict2}
print(dict3)


# 输出结果
{‘a‘: 1, ‘b‘: 2, ‘name‘: ‘yy‘, ‘age‘: 22}