python lambda函数如何使用

f=lambda [parameter1,parameter2,……]:expression

f=lambda :'python lambda!'

>>> f

<function <lambda> at 0x06BBFF30>

>>> f()

'python lambda!'

f=lambda x,y:x+y

>>> f(3,4)

7

f=lambda x=2,y=8:x+y

>>> f

<function <lambda> at 0x06C51030>

>>> f()#x取默认值2，y取默认值8

10

>>> f(1)#x取1，y取默认值8

9

>>> f(3,3)#x,y均取值3

6

sumxy=lambda x,y:x+y

def test(f,m,n):

  print f(m,n)

>>> sumxy(4,5)

9

>>> test(sumxy,4,5)

9