switch 与 python字典

python 中并没有switch语句，但是有一个数据类型与switch语句特别相似，它就是 dict{ key: value, ...}

下面用 dict{ key:value,..} 来简单的实现switch语句：

#!/usr/bin/env python
#coding:utf-8

from __future__ import division

__version__ = 1.0

def jia(x, y, *args, **kwargs):
    return x + y

def jian(x, y, *args, **kwargs):
    return x - y

def cheng(x, y, *args, **kwargs):
    return x * y

def chu(x, y, *args, **kwargs):
    return x / y

operator = {"+":jia, "-":jian, "*":cheng, "/":chu}  #核心

def fun(o, x, y):
    print operator.get(o)(x, y)

fun("+",3, 6)