官方教程0:https://docs.python.org/3.4/howto/regex.html#regex-howto
官方教程1:https://docs.python.org/3.4/library/re.html?highlight=re#
#!/usr/bin/env python
# coding: utf-8
#copyRight by heibanke
import re
text = 'c++ python2 python3 perl ruby lua java javascript php4 php5 c'
#match,search,findall,split,sub
re.match(r'c++',text)
re.match(r'c++',text)
re.match(r'java',text)
re.search(r'java',text)
print re.findall(r'python',text)
print re.split(r' perl ',text)
print re.sub(r'ruby','fortran',text)
# + 1-inf
# * 0-inf
# ? 0-1,
# [] or
# {} repeat
# [^] not
print re.findall(r'p+',text)
print re.findall(r'p[a-zA-Z]+',text) #{1,}
print re.findall(r'c[a-zA-Z]*',text) #{,inf}
print re.findall(r'c[^a-zA-Z]*',text) #{,inf}
print re.findall(r'c[a-zA-Z]?',text) #{,1}
# | or
print re.findall(r'[pj][a-zA-Z]+',text) #{,inf}
print re.findall(r'p[^0-9]+|j[a-zA-Z]+',text)
print re.findall(r'p[^0-9 ]+|j[a-zA-Z]+',text)
# ^ start
# $ end
# . except
print re.findall(r'^c..',text)
print re.findall(r'c+',text)
print re.findall(r'c++',text)
print re.findall(r'c$',text)
# w [a-zA-Z0-9_], W [^a-zA-Z0-9]
# d [0-9], D
# s [
fv], S
print re.findall(r'pw+',text)
print re.findall(r'pw+d',text)
print re.findall(r'pw+[0-9]',text)
print re.findall(r'pw{5,9}',text)
# word boundary
# B not
# A input start, ^
# input end, $
print re.findall(r'p[^0-9]',text)
print re.findall(r'p[^0-9]',text)
# *? 0~inf non-greedy
# +? 1~inf non-greedy
print re.findall(r'p[^0-9]*',text)
print re.findall(r'p[^0-9]*?',text)
print re.findall(r'p[^0-9]+',text)
print re.findall(r'p[^0-9]+?',text)
# () group
# (?P<name>pattern)
a=re.search(r'(p[a-zA-Z]+)([0-9])','python2')
print a.group(1), a.group(2)
a=re.search(r'(?P<name>p[a-zA-Z]+)(?P<version>[0-9])','python2')
print a.group('name'), a.group('version')
print a.groupdict()
pattern = re.compile(r'(?P<name>p[a-zA-Z]+)(?P<version>[0-9])')
results = pattern.search('python2')
print results.groupdict()
results = pattern.search('python3')
print results.groupdict()
results = pattern.search('php4')
print results.groupdict()
#########################################
for t in text.split(' '):
results = pattern.search(t)
if results:
print results.groupdict()