The regular-expressions tag has no wiki summary.
10
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7answers
3k views
How do regular expressions actually work?
Say you have a document with an essay written. You want to parse this essay to only select certain words. Cool.
Is using a regular expression faster than parsing the file line by line and word by ...
0
votes
1answer
300 views
Why nginx's http parser doesnt use regular expressions?
I see the http parser written by Igor Sysoev for nginx does not use regular expressions
https://github.com/joyent/http-parser
What could be the main reason for such design decision? I guess I could ...
19
votes
3answers
1k views
Are regular expressions a programming language?
In the academic sense, do regular expressions qualify as a programming language?
The motivation for my curiosity is an SO question I just looked at which asked "can regex do X?" and it made me wonder ...
47
votes
10answers
3k views
Readable regular expressions without losing their power?
Many programmers know the joy of whipping up a quick regular expression, these days often with help of some web service, or more traditionally at interactive prompt, or perhaps writing a small script ...
7
votes
10answers
841 views
A better way of doing Regex? [duplicate]
I really dislike regular expressions, each time I come back to it I seem to have to relearn it. It's also incredibly hard to maintain, modify and at a glance understand what it is doing.
Has anyone ...
5
votes
11answers
1k views
Decent tool for building and testing regular expressions [duplicate]
I'm in need of a decent tool for building and testing regular expressions, what does everyone use?
I would download expresso but in my last place it turned out to be laden with adware - any clean ...
5
votes
3answers
251 views
Constructing a Finite State Automaton
I have an exam question that I am unsure of the answer. The question is:
In organisation X valid user names have the following structure. The
user name can be either the employee’s name followed ...
3
votes
1answer
474 views
Constructing a Deterministic Finite State Automaton for a given Regex
I have a couple of exam questions for my compilers class and wanted to check if my solutions are correct.
The first question is:
Consider a language in which numbers start with an optional minus
...
-1
votes
2answers
170 views
Can non-IT people learn and take advantage of regular expressions? [closed]
Often times, not-IT people has to deal with massive text data, clean it, filter it, modify it. Often times normal office tools like Excel lack the tools to make complex search and replace operations ...
0
votes
2answers
254 views
Documentation often ommits to specify which flavour of regular expression to use, so is there a default flavour that we should all be familiar with?
Often I come across documentation that says "use a regular expression here" I have to spend quite some time digging around trying to work out which regular expression format they are expecting.
As ...
2
votes
1answer
81 views
String patterns that can be used to filter and group files
One of our application filters files in certain directory, extract some data from it and export a document from the extracted data. The algorithm for extracting the data depends on the file, and so ...
63
votes
23answers
10k views
Is it a must for every programmer to learn regular expressions?
I am new to programming, and at an interview I got a question on regular expressions; needless to say I couldn't answer. So I was wondering whether I should learn regular expression? Is it a must for ...
3
votes
1answer
685 views
can a regex search engine for the web be done and if so, how?
I think it would be a great idea if we had a regular expression search engine, but can it be done? It seems impossible since there's no feasible way of indexing such a huge amount of data properly and ...
2
votes
2answers
114 views
What is the best strategy for transforming unicode strings into filenames?
I have a bunch (thousands) of resources in an RDF/XML file. I am writing a certain subset of the resources to files -- one file for each, and I'm using the resource's title property as the file name. ...
5
votes
2answers
245 views
Python flavor of regular expressions - related to which?
So my copy of the classic book, Mastering Regular Expressions, just arrived, and I'm scanning through it. The cover (third edition) says, "for Perl, PHP, Java, .NET, Ruby, and More!" Well, it does ...
