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Python Regular Expressions in Python Introduction to Regular Expressions Email Groups

Zoltan Onody
Zoltan Onody
7,491 Points
Posted by Zoltan Onody
Zoltan Onody
7,491 Points

What is the difference between these 2 regular expressions?

Hey, I have these 2 different regex...

1) (?P<email>[-\w\d.\+]+@[\w\d.]+)

2) (?P<email>[\w\d.-\+]+@[\w\d.]+)

The first is working properly but the second throws "bad character range" error, why? I thought that the order of characters don't matter.

1 Answer

Geoff Parsons
Geoff Parsons
11,679 Points

In the second one you'll need to escape the "-". It's attempting to create a range from \d - \+ which doesn't make sense; typically this is use for things like [0-9] or [A-Z]. And you'll need to escape the "." as it will attempt to match any character thus making your character set kind of useless.

Edit: As Kenneth Love pointed out below "." in a set doesn't match any character, it only matches periods. Edited to remove bogus info.

Kenneth Love
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

. in a [set] does not attempt to match any character, it only matches periods.

Geoff Parsons
Geoff Parsons
11,679 Points

Eep! My bad Kenneth Love!