Using Regexp to catch substring python

Question

Let's assume I have some string like that:

x = 'Wish she could have told me herself. @NicoleScherzy #nicolescherzinger #OneLove #myfav #MyQueen :heavy_black_heart::heavy_black_heart: some string too :smiling_face:' 

So, I want to get from that :

:heavy_black_heart:
:smiling_face:

To do that I did the following :

import re
result = re.search(':(.*?):', x)
result.group()

It only gives me the ':heavy_black_heart:' . How could I make it work ? If possible I want to store them in dictonary after I found all of them.

Answer 1

print re.findall(':.*?:', x) is doing the job.

Output:
[':heavy_black_heart:', ':heavy_black_heart:', ':smiling_face:']

But if you want to remove the duplicates:

Use:

res = re.findall(':.*?:', x)
dictt = {x for x in res}
print list(dictt)

Output:
[':heavy_black_heart:', ':smiling_face:']

Answer 2

You seem to want to match smilies that are some symbols in-between 2 : s. The .*? can match 0 symbols, and your regex can match :: , which I think is not what you would want to get. Besdies, re.search only returns one - the first - match, and to get multiple matches, you usually use re.findall or re.finditer .

I think you need

set(re.findall(r':[^:]+:', x))

or if you only need to match word chars inside :...: :

set(re.findall(r':\w+:', x))

or - if you want to match any non-whitespace chars in between two : :

set(re.findall(r':[^\s:]+:', x))

The re.findall will find all non-overlapping occurrences and set will remove dupes.

The patterns will match : , then 1+ chars other than : ( [^:]+ ) (or 1 or more letters, digits and _ ) and again : .

>>> import re
>>> x = 'Wish she could have told me herself. @NicoleScherzy #nicolescherzinger #OneLove #myfav #MyQueen :heavy_black_heart::heavy_black_heart: some string too :smiling_face:'
>>> print(set(re.findall(r':[^:]+:', x)))
{':smiling_face:', ':heavy_black_heart:'}
>>> 

Answer 3

试试这个正则表达式：

:([a-z0-9:A-Z_]+):

Answer 4

import re
x = 'Wish she could have told me herself. @NicoleScherzy #nicolescherzinger #OneLove #myfav #MyQueen :heavy_black_heart::heavy_black_heart: some string too :smiling_face:' 
print set(re.findall(':.*?:', x))

output:

{':heavy_black_heart:', ':smiling_face:'}

Answer 5

Just for fun, here's a simple solution without regex. It splits around ':' and keeps the elements with odd index:

>>> text = 'Wish she could have told me herself. @NicoleScherzy #nicolescherzinger #OneLove #myfav #MyQueen :heavy_black_heart::heavy_black_heart: some string too :smiling_face:'
>>> text.split(':')[1::2]
['heavy_black_heart', 'heavy_black_heart', 'smiling_face']
>>> set(text.split(':')[1::2])
set(['heavy_black_heart', 'smiling_face'])