def greet(name, age, city):
    print(f"{name}, {age}歲, 來(lái)自{city}")

args = ["Alice", 20, "Beijing"]

greet(*args)
# 等價(jià)于 greet("Alice", 20, "Beijing")

point = (10, 20)

def draw(x, y):
    print(x, y)

draw(*point)   # draw(10, 20)

def foo(a, b, c):
    print(a, b, c)

foo(1, *[2, 3])       # foo(1, 2, 3)
foo(*[1, 2], 3)       # ? 語(yǔ)法錯(cuò)誤，* 解包段必須在最后或單獨(dú)使用
foo(1, *[], 3)        # ? 同上

rest = [2, 3]
foo(1, *rest)          # ? a=1, b=2, c=3

def foo(*args):
    print(args)
    print(type(args))

foo(1, 2, 3)
# (1, 2, 3)
# <class 'tuple'>

nums = range(1, 4)     # range 對(duì)象
list(*nums)            # ? range 不能直接 * 給 list()
print(*nums)           # ? print(1, 2, 3)

def total(a, b, c):
    return a + b + c

total(*[10, 20, 30])   # 60

def greet(name, age):
    print(f"name={name}, age={age}")

info = {"name": "Alice", "age": 20}

greet(**info)
# 等價(jià)于 greet(name="Alice", age=20)

def foo(**kwargs):
    print(kwargs)

foo(a=1, b=2)
# {'a': 1, 'b': 2}

filtered = {"max_step_num": 5}

cls(**filtered)
# 等價(jià)于 Configuration(max_step_num=5)

return cls(**{k: v for k, v in values.items() if v})

def foo(a, b, *args, **kwargs):
    print("a, b =", a, b)
    print("args  =", args)
    print("kwargs=", kwargs)

foo(1, 2, 3, 4, x=10, y=20)
# a, b = 1 2
# args  = (3, 4)
# kwargs= {'x': 10, 'y': 20}

def foo(a, b, c, x, y):
    print(a, b, c, x, y)

pos = [3, 4]
kw = {"x": 10, "y": 20}

foo(1, 2, *pos, **kw)
# foo(1, 2, 3, 4, x=10, y=20)
# 輸出: 1 2 3 4 10 20

def connect(host, port, *, timeout=30, ssl=True):
    ...

connect("localhost", 3306, timeout=60)   # ?
connect("localhost", 3306, 60)             # ? timeout 必須用 timeout=60

a = [1, 2]
b = [3, 4]
c = [*a, *b]           # [1, 2, 3, 4]

a = {"x": 1}
b = {"y": 2}
c = {**a, **b}         # {"x": 1, "y": 2}

b = {"x": 99}
{**a, **b}             # {"x": 99}  后面的覆蓋前面的

def wrapper(*args, **kwargs):
    print("調(diào)用前")
    result = original_func(*args, **kwargs)   # 原樣轉(zhuǎn)發(fā)
    print("調(diào)用后")
    return result

def foo(a, b):
    pass

foo(*[1, 2, 3])   # ? TypeError: too many arguments
foo(**{"a": 1})   # ? TypeError: missing b

foo(**{"max-step": 5})   # ? key 帶橫線，不能當(dāng)參數(shù)名
foo(**{"max_step_num": 5})  # ?

def foo(a, b):
    pass

foo(1, *[2, 3])          # ?
foo(1, b=2, *[3])        # ? b 傳了兩次
foo(1, **{"a": 99})      # ? a 傳了兩次

2 * 3        # 乘法 → 6
func(*[2, 3])  # 解包 → 傳入兩個(gè)參數(shù) 2 和 3

# 練習(xí) 1：用 * 解包
def add(a, b, c):
    return a + b + c
print(add(*[1, 2, 3]))   # 6

# 練習(xí) 2：用 ** 解包
def profile(name, age):
    return f"{name}-{age}"
print(profile(**{"name": "Tom", "age": 18}))  # Tom-18

# 練習(xí) 3：模擬項(xiàng)目
def fake_config(**kwargs):
    print(kwargs)
fake_config(**{"max_step_num": 5, "locale": "zh-CN"})

foo(*[1, 2, 3])              # 位置：foo(1, 2, 3)
foo(**{"a": 1, "b": 2})      # 關(guān)鍵字：foo(a=1, b=2)
cls(**{"max_step_num": 5})   # Configuration(max_step_num=5)