Python 复制与赋值

用‘b=a’复制，对变量a,b的操作都会对a指向的对象起作用。

用‘b=a[]’赋值，则只是赋值。

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Filename:reference.py

__author__ = 'JerryQiu'

print 'Simple Assignment'
shoplist = ['apple','mango','carrot','banana']
mylist = shoplist

del mylist[0]

print 'shoplist is:',shoplist
print 'mylist is:',mylist

print 'Copy by making a full slice'
mylist= shoplist[:]
del shoplist[0]

print 'shoplist is:',shoplist
print 'mylist is:',mylist

$python reference.py

Simple Assignment
shoplist is: ['mango', 'carrot', 'banana']
mylist is: ['mango', 'carrot', 'banana']
Copy by making a full slice
shoplist is: ['carrot', 'banana']
mylist is: ['mango', 'carrot', 'banana']