How do I print matches from a regex given a string value in Python?-CodePudding

I have the string "/browse/advanced-computer-science-modules?title=machine-learning"** in Python. I want to print the string in between the second "/" and the "?", which is "advanced-computer-science-modules".

I've created a regular expression that is as follows ^([a-z]*[\-]*[a-z])*?$ but it prints nothing when I run the .findall() function from the re module.

I created my own regex and imported the re module in python. Below is a snippet of my code that returned nothing.

regex = re.compile(r'^([a-z]*[\-]*[a-z])*?$')
str = '/browse/advanced-computer-science-modules?title=machine-learning'
print(regex.findall(str))

CodePudding user response：

Since this appears to be a URL, I'd suggest you use URL-parsing tools instead:

>>> from urllib.parse import urlsplit
>>> url = '/browse/advanced-computer-science-modules?title=machine-learning'
>>> s = urlsplit(url)
SplitResult(scheme='', netloc='', path='/browse/advanced-computer-science-modules', query='title=machine-learning', fragment='')
>>> s.path
'/browse/advanced-computer-science-modules'
>>> s.path.split('/')[-1]
'advanced-computer-science-modules'

CodePudding user response：

The regex is as follows:

\/[a-zA-Z\-] \?

Then you catch the substring:

regex.findall(str)[1:len(str) - 1]

Very specific to this problem, but it should work.

CodePudding user response：

Alternatively, you can use split method of a string:

str = '/browse/advanced-computer-science-modules?title=machine-learning'
result = str.split('/')[-1].split('?')[0]

print(result)
#advanced-computer-science-modules