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Python

Posted by Ferenc Vámos
Ferenc Vámos
5,047 Points

Few questions

line = (re.search(r'''
    ^(?P<name>[-\w ]*,\s[-\w ]+)\t  # Last and first names
    (?P<email>[-\w\d.+]+@[-\w\d.]+)\t  # Email
    (?P<phone>\(?\d{3}\)?-?\s?\d{3}-\d{4})?\t  # Phone number
    (?P<job>[\w\s]+,\s[\w\s.]+)\t?  # Job and company
    (?P<twitter>@[\w\d]+)?$  # Twitter
''', data, re.X|re.MULTILINE))

  1. How come that if I make one typo in the re.findall()/re.search it returns an empty list? Why doesn't it just skip over the part with the error, for example the e-mails?

  2. The created tuples have one from each of my groups in case of using re.findall() instead of re.search(), specified between parentheses, am I correct?

  3. How come .gropudict() works, but this code doesn't? Doesn't re.search() return a dictionary? What exactly is the difference between .groupdict() and my (wrong) solution?

for key, value in line.items():
    print(f"{key}: {value}")
Ferenc Vámos
Ferenc Vámos
5,047 Points

Found this resource which mostly clears up my third question. I'll leave the URL here if anyone has the same issue link

1 Answer

AJ Tran
STAFF
AJ Tran
Treehouse Teacher
AJ Tran
AJ Tran
Treehouse Teacher

To answer your first question

  1. How come that if I make one typo in the re.findall()/re.search it returns an empty list? Why doesn't it just skip over the part with the error, for example the e-mails?

When the computer reads your code, it will give you exactly what you ask of it. If your code is syntactically correct, the computer will just run the whole thing, even if there is a "logical" error like a small "variation" in a RegEx. So you get an empty list because there is nothing found with that pattern you specified.

This is one of the "features" of programming -- the computer just does what you tell it to! So to answer your second question, it will not skip the "variation" because you did not give it instructions to skip it.

I am calling it a "variation" instead of an error because there is a branch of programming you can learn called "exception handling" which deals exactly with catching errors and running "a backup plan" for when there is an error. But in this case, an "error" will be something that will otherwise cause your program to crash. :)