[Python知识库]函数式编程

匿名函数

#匿名函数

def add(x,y):

????return x + y

print(add(1,2))

f = lambda x,y:x+y

print(f(1,2))

Python中的三元表达式： x if x > y else y

其它语言中的三元表达式：x > y ? x : y

map:其实就是一种映射。

如：

#map

list_x = [1,2,3,4,5,6,7,8]

list_y = [1,2,3,4,5,6,7,8]

r = map(lambda x,y:x*x + y,list_x,list_y)

print(list(r))

from functools import reduce

#连续计算，连续调用lambda

list_x = [1,2,3,4,5,6,7,8]

r = reduce(lambda x,y :x+y,list_x)

print(r)

map/reduce 编程模型 映射 归约 ?并行计算

函数式编程

filter:过滤

#filter

list_x = [1,0,1,0,0,1]

r = filter(lambda x:True if x==1 else False,list_x)

print(list(r))

#装饰器

import time

def f1():

????print(time.time())

????print('This is a function')

????

f1()

import time

def decorator(func):

????#key word

????def wrapper(*args,**kw):

????????print(time.time())

????????func(*args,**kw) ?#是一种抽象的调用方式

????return wrapper

@decorator

def f1(func_name):

????print('This is a function named'+func_name)

@decorator

def f2(func_name1,func_name2):

????print('This is a function named'+func_name1)

????print('This is a function named'+func_name2)

@decorator

def f3(func_name1,func_name2,**kw):

????print('This is a function named'+func_name1)

????print('This is a function named'+func_name2)

????print(kw)

????

f3('test func1','test func3',a = 1,b = 2, c = '123')

@api.route('/get',methods = ['GET'])

def test_javascript_http():

????p = request.args.get('name')

????return p,200

@api.route('/psw',methods = ['GET'])

@auth.login_required

def get_psw():

????p = request.args.get('pws')

????r = generate_password_hash(p)

????return 'aaaaaa',200