The regex tag has no wiki summary.
1
vote
0answers
73 views
Is there any efficient Java solution/Algorithm to find values in a text field based on key string with delimiter? [migrated]
Is there any efficient Java solution/Algorithm to find values in a text field based on key string with delimiter?
Example:
Rules:
I. Key: username Start-Delimiter: ; End-Delimiter: ;
Need to find ...
2
votes
3answers
157 views
Domain-specific language for text search/processing?
I work for an organization that does a lot of work with government data. We have a couple of different projects where we've abstracted out common text search/manipulation operations into reusable ...
2
votes
1answer
135 views
How to choose a proper parser generator for PHP
Some programmers avoid regexes in some situations (see this popular @nickf comment), perhaps using a parsing framework such as Lex/Yacc. Others prefer to stay within PHP, perhaps using regular ...
3
votes
1answer
366 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
...
4
votes
4answers
779 views
Can the csv format be defined by a regex?
A colleague and I have recently argued over whether a pure regex is capable of fully encapsulating the csv format, such that it is capable of parsing all files with any given escape char, quote char, ...
0
votes
2answers
151 views
How should a website validate a users mailing address?
This is for a site that relies on shipping items via UPS or FedEx. I know there is software out there that does it (http://en.wikipedia.org/wiki/Coding_Accuracy_Support_System), but if you are trying ...
5
votes
2answers
220 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 ...
7
votes
5answers
460 views
Lexical Analysis without regular expressions
I've been looking at a few lexers in various higher level langauges (Python, PHP, Javascript among others) and they all seem to use regular expressions in one form or another. While I'm sure regex's ...
8
votes
7answers
2k 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 ...
2
votes
4answers
230 views
Maintaining Regex in a .net application
I am sure everybody has had his/her share of regex woes.
We have a big application with around 30 developers working on a mvc3 web application , and the two fold regex validations (front-end and ...
13
votes
10answers
716 views
Inspiring problems to show off the importance of regular expressions?
I am planning to give a presentation/demonstration on regular expressions at work to encourage young developers to add this powerful and important tool in their toolbox.
Just teaching syntax doesn't ...
77
votes
18answers
4k views
How do you learn Regular Expressions?
I'm not asking where to learn. I've found lots of good resources online, and books etc.
But how the heck do I tackle them. Where is the start of it, the end? When does the regexp processor advance on ...
11
votes
7answers
626 views
What is more standard shortening for “regular expression”, “regex” or “regexp”? [closed]
I want to know what is more standard way to call regular expression in short way. I have seen both, regex and regexp.
Google says regex has almost 2 as much hits that regexp, but it depends on way I ...
4
votes
2answers
279 views
Using lookahead assertions in regular expressions
I use regular expressions on a daily basis, as my daily work is 90% in Perl (legacy codebase, but that's a different issue). Despite this, I still find lookahead and lookbehind to be terribly ...
12
votes
6answers
393 views
What can / should be done with regular expressions?
I've recently learnt regular expressions and I love writing / using them. I'm looking for ideas and more opportunities to use them, however I don't want to overuse them as an all purpose tool, as ...
3
votes
1answer
642 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 ...
7
votes
6answers
557 views
Resources for Learning Regular Expressions [closed]
What are the best resources you've found for learning regular expressions?
0
votes
2answers
224 views
Regexp or custom parsing algo?
I was trying to parse a java properties file to avoid some Properties loading pitfalls (non ordering, loss of comments).
(Property are of the form 'key = value' where the value can span on multiple ...
34
votes
10answers
3k views
What does the Jamie Zawinski's quotation about regular expressions mean?
In a message to comp.emacs.xemacs, Jamie Zawinski once said:
Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems.
I've always ...
65
votes
24answers
8k views
How far should one take e-mail address validation?
I'm wondering how far people should take the validation of e-mail address. My field is primarily web-development, but this applies anywhere.
I've seen a few approaches:
simply checking if there is ...
