Many tool in the web help us to leverage the regex (lets list just https://regex101.com/ to try live the patterns and http://rexegg.com/ to learn how construct a regex).
So, what’s a regex? A regular expression, i.e., quoting http://rexegg.com/:
A regex is a text string that describes a pattern that a regex engine uses in order to find text (or positions) in a body of text, typically for the purposes of validating, finding, replacing or splitting.
But what if you need a python regex?
Then you pass trough the re module (and import re line https://docs.python.org/3/library/re.html ) and special objects (in Python everything is an object), like Match object .
Methods or attributes of a Match object are:
.span() returns a tuple containing the start-, and end positions of the match.
.string returns the string passed into the function
.group() returns the part of the string where there was a match
To fast refer to the example, you can access this page: https://code.sololearn.com/c7P2n5x2CmYO
1. Greedy and Lazy Matching
The ? symbol, inside of a pattern, can mean many things. One of these is “have a lazy behavior”.
Id est, consider this example:
Have a look to
The method findall is the “simplest” for us. Do you search the regex to find something? Well, re.findall(pattern, string) returns you a list with this something.
3. search() Function
The search() function searches the string for a match, and returns
If you’re a fan of list comprehension. have a look here https://stackoverflow.com/questions/2436607/how-to-use-re-match-objects-in-a-list-comprehension .