question tuples in regex -regular expressions - python-3.x

Question

So I have some code on which I will use an regex on.
Specifically, I need to use re.findall() and a single regular expression to extract the three names and email addresses from the 'string'. To create list of 3 tuples like so: [('Mary Boe', 'md90#uw.com'), ('Cheri Moe Drake', 'cmd39#gmail.gbl'), ('R.L. Fitzgeri', 'fit.rl#hotmail.ing')]
here is the string....
string = """Name: Mary Boe, Email: md90#uw.com\n
Name: Cheri Moe Drake, Email: cmd39#gmail.gbl\n
Name: R.L. Fitzgeri, Email: fit.rl#hotmail.ing"""
So far I have used the following to get ['R.L. Fitzgeri']
with
re.findall('\S\S\w\S\s\w\S\w\w\w\w\S\w',string)
And I have been able to get fit.rl#hotmail.ing
with
re.findall('\w\\w\\w\\S\w\w\S\w\w\w\w\S\w\w\S\w\w\w',string)
I have been able to get Cheri Moe Drake with
re.findall('\w\w\w\w\w\s\w\w\w\s\w\w\w\w\w',string)
But I have struggled condensing this, and secondly, struggled to get it so that it all comes out, as I said, like:
[('Mary Boe', 'md90#uw.com'), ('Cheri Moe Drake', 'cmd39#gmail.gbl'), ('R.L. Fitzgeri', 'fit.rl#hotmail.ing')]

Answer 1

Here is a way to do the job:
import re
string = """Name: Jane Doe, Email: jd12#uw.com\n
Name: Sally Sue Draper, Email: ssd59#gmail.edu\n
Name: J.D. Salinger, Email: sal.jd#hotmail.org"""
pattern = r'Name: (.+?), Email: (.+)'
result = re.findall(pattern, string)
print(result)
Output:
[('Jane Doe', 'jd12#uw.com'), ('Sally Sue Draper', 'ssd59#gmail.edu'), ('J.D. Salinger', 'sal.jd#hotmail.org')]
Regex explanation:
Name: # literally
(.+?) # group 1, 1 or more any character but newline, not greedy
, Email: # literally
(.+) # group 2, 1 or more any character but newline

Answer 2

If you always have the same format, it may make more sense to avoid regular expressions in this scenario and approach the problem alternatively:
string = """Name: Jane Doe, Email: jd12#uw.com\n
Name: Sally Sue Draper, Email: ssd59#gmail.edu\n
Name: J.D. Salinger, Email: sal.jd#hotmail.org"""
people = [person for person in string.split('\n') if person]
people_list = []
for person in people:
name = ''
for char in person[6:]:
if char == ',':
break
else:
name += char
email = ''
for char in person[::-1]:
if char == ' ':
break
else:
email += char
email = email[::-1]
person_tuple = (name, email)
people_list.append(person_tuple)
This will give you a list of tuples if you print people_list:
[('Jane Doe', 'jd12#uw.com'), ('Sally Sue Draper', 'ssd59#gmail.edu'), ('J.D. Salinger', 'sal.jd#hotmail.org')]
This assumes that all your lines start with Name:, which is why the loop builds a name by concatenating all characters after that up to the first comma it finds.
For the email, it does the same thing in reverse: it takes all characters starting from the end of the string until it finds a space, where the email is effectively ending. It then puts it back in order to get the correct email.
To build the list of contacts, the loop will format name and email into a tuple that will be appended to people_list until there are no more contacts to add.
If you insist on using regular expressions, then a good use for those could be if you want to validate email addresses and not add a contact to your list if the email does not correspond to the format of your choosing (or leave it blank instead). The regex pattern could look like this:
email = 'example#email.com'
pattern = r'[a-z]+[a-z0-9]*[\w._-]*#[a-z]+\.[a-z]{1,3}$'
if re.match(pattern, email):
# do something with email here
Note that in this case, the regex uses symbols like + and * to avoid repetition, which is one of the keys in building a more robust regex.