python 偏函数

偏函数（functools.partial）

可代为传递参数

示例1

def func(a1,a2,a3):
    return a1 * a2 * a3

import functools

f1 = functools.partial(func,111)
f2 = functools.partial(func,222)
v1 = f1(2,3)
v2 = f2(2,3)

print(v1,v2)    # 116 227

示例2

import functools

class RequestContext(object):
    def __init__(self):
        self.request = 'aaaaa'
        self.session = 'bbbbb'
obj = RequestContext()

def get_data(name):
    return getattr(obj,name)

request_proxy = functools.partial(get_data,'request')
session_proxy = functools.partial(get_data,'session')

request = request_proxy()
session = session_proxy()

print(request,session)    # aaaaa bbbbb