python之匿名函数lambda

# lambda：匿名函数
# 语法：lambda 参数: 表达式

answer = lambda x: x * 5
print("answer(5): ", answer(5))  # answer(5):  25


# lambda做为参数
def fun_test(x=lambda x: x * 5):
    return x(5)


n = fun_test(lambda x: x * 6)
print("x(5): ", n)  # x(5):  30

# lambda 列表元素
y = [lambda x: x * x, 2, 3]
print(y[0](y[1]))  # 4

mapped = map(lambda x: ord(x) + 10, "hello")
print(list(mapped))  # [114, 111, 118, 118, 121]

li = filter(lambda x: x % 2, range(10))
print(list(li))  # [1, 3, 5, 7, 9]