ex8~ex10变量与转义序列

先贴上这几课的代码
ex8

#-*- coding:utf-8 -*-
formatter = "%s %r %r %r" #定义字符串，字符串里嵌套格式化字符串

print formatter % (1,2,3,4) # 1234会替换字符串里的%r
print formatter % ('one','two','three','four')
print formatter % (True,False,True,False)
print formatter % (formatter,formatter,formatter,formatter) #每个formatter都是一个包含四个%r的字符串
print formatter % (
    "我是",
    "That you could type up right.",
    "But it didn't sing.",
    "So I said goodnight.")

ex9

days = "Mon Tue Wed Thu Fri Sat Sun"
months = "Jan\nFeb\nMar\nApr\nMay\nJun\nJul\nAug"

print "Here are the days:", days
print "Here are the months:", months

print """
There's something going on here.
With the three double-quotes.
We'll be able to type as much as we like.
Even 4 lines if we want, or 5, or 6.
"""

ex10

tabby_cat = "\tI'm tabbed in."
persian_cat = "I'm split\non a line."
backslash_cat = "I'm \\ a \\ cat."

fat_cat = """
I'll do a list:
\t* Cat food
\t* Fishies
\t* Catnip\n\t* Grass
"""

print tabby_cat
print persian_cat
print backslash_cat
print fat_cat

这几课的新知识是转义序列的应用

转义字符.png

有个小问题先放在这里，\r与\n 有什么别，感觉都能实现换行的作用啊？