re.match('z', 'az') returns None [duplicate] - python

This question already has answers here:
What is the difference between re.search and re.match?
(9 answers)
Closed 1 year ago.
See title. The behavior here is counterintuitive. I think maybe I am missing some flags or something? Why does the regex z not match the string az?

The reason is that match only matches the beginning of a string. Must use search to do the thing that match would do in all other programming languages.
Sorry to throw shade at you Python, but you're the odd one out here.

Related

Example of Match.expand usage [duplicate]

This question already has answers here:
Use Python Match object in string with backreferences
(1 answer)
Regex in python: is it possible to get the match, replacement, and final string?
(2 answers)
Closed 3 years ago.
What is an example usage of Match.expand ? It doesn't give any examples in the python docs (which is the first I've heard of the method), and only states:
Match.expand(template)
Return the string obtained by doing backslash substitution on the template string template, as done by the sub() method.
How would this actually be used and how could it be useful?
you can find more explanations and examples here:
match.expand
In general:
it allows you to expand the match you have found and modify its' prefix

What are () (parentheses) are for in regex python [duplicate]

This question already has answers here:
Python regex -- extraneous matchings
(5 answers)
Closed 6 years ago.
I searched in all the internet and didnt get a good answer on this thing.
What parentheses in python are stand for? its very wierd..
For example, if i do:
re.split(r'(/s*)', "ho from there")
its will give me a list of separate words with the spaces between that... how does its happening?
This isn't specific to python, but in regex those denote a capture group.
Further information on how these are handled in re.split can be seen here

Ruby's "next" implementation in Python [duplicate]

This question already has answers here:
How can I get the next string, in alphanumeric ordering, in Python?
(4 answers)
Closed 6 years ago.
If Python has an implementation of Ruby's next method? I mean something what works exactly the same as in Ruby, so if I type e.g. "z".next it will return "aa" (instead of just next sign in ascii table), "az".next will return "ba" and so on.
I don't believe there is a built-in method for this in Python. A similar question was asked on How can I get the next string, in alphanumeric ordering, in Python? and the accepted answer gives a solution.

re.match in python to match pattern with string [duplicate]

This question already has answers here:
What is the difference between re.search and re.match?
(9 answers)
Closed 7 years ago.
I am trying to match string with mypattern, somehow I do not get correct result. Can you please point where am I wrong?
import re
mypattern = '_U_[R|S]_data.csv'
string = 'X003_U_R_data.csv'
re.match(mypattern, string)
I like to compile the regex statement first. Then I do whatever kind of matching/searching I would like.
mypattern = re.compile(ur'_U_[R|S]_data.csv')
Then
re.search(mypattern, string)
Here's a great website for regex creation- https://regex101.com/#python

unable to match this regular expression in python [duplicate]

This question already has an answer here:
Reference - What does this regex mean?
(1 answer)
Closed 4 years ago.
I am trying to match regular expression using python in this code.
CDS_REGEX = re.compile(r'\+CDS:\s*"([^"]+)",\s*(\d+)$')
cdsiMatch = allLinesMatchingPattern(self.CDS_REGEX, notificationLine)
print cdsiMatch
Matching String:
['+CDS: 24', '079119890400202306A00AA17909913764514010106115225140101061452200']
Please help me i am not able to find my mistake,
As #Blckknght said, are you sure you really want to match that string?
What is ([^"]+) supposed to match?
You're looking for " instead of ' (you probably want ['"]).
You're only checking for numbers here: (\d+), but your long string clearly contains A's.

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