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# Can someone explain the + well for me

In search = r"[-\w\d+.]+@[-\w\d+]+" why do we need to add + in the set and outside of the set. What are we saying when we add it and not add it

I thought + sign inside first [] is just intended to catch doctor's email address which has '+' inside it.

doctor+companion@tardis.co.uk

However, + sign outside [] means 'match any character inside [], once or more'

I'm not confident but it seems right...

example:

```>>> text = "2+4 you+me"

# []+ searches for 1 or more of whatever is inside []
>>> re.findall(r'\b[\w]+\b', text)
['2', '4', 'you', 'me']

# [+] searches for '+' in text
>>> re.findall(r'\b[\w+]\b', text)
['2', '+', '4', '+']

# both inside and out
>>> re.findall(r'\b[\w+]+\b', text)
['2+4', 'you+me']
```

Inside your square brackets, you're defining the group of allowed characters in the string that you're looking for, i.e. dashes (-), word characters (\w), numbers (\d), plus signs (+) and points (.). Outside the square brackets, when you use the plus sign, you're saying that there can be any number of any of the group of allowed characters in that string.

It's a small difference, but an important one.

Can you please explain with examples. What do you mean allow in any group of characters?

Welby, I suggest that you re-watch the video, Kenneth Love covers that during the lectures with examples.

William I tried that already...thank you

I want to know the difference in the + in the set vs the + outside the set