Regular expressions are a declarative language, mainly used for pattern matching within strings. Please include a tag specifying the programming language you are using, together with this tag.
7
votes
1answer
88 views
How could I improve this map-reduce code?
I have been changing this code and I don't get to make it much better, I changed a little bit the structure, reimplemeted a new function for splitting Strings which is more efficient, etc. I have been ...
3
votes
2answers
38 views
Help in deciding how to represent a long regular expression
I wrote a simple Polynomial class:
class Polynomial
def initialize(coefficients)
@coefficients = coefficients.reverse
end
def to_s
return '0' if @coefficients.all?(&:zero?)
...
1
vote
1answer
28 views
TCPDUMP file (part of a real capture)
I have been working on this code for quite a while and just want to make sure it is up to good standards. I know many of you will have questions, so as they come up, I will edit my initial question to ...
3
votes
2answers
60 views
Either or case in Python and Regex
I have a small module that gets the lemma of a word and its plural form. It then searches through sentences looking for a sentence that contains both words (singular or plural) in either order. I have ...
2
votes
3answers
179 views
Convert Sql LIKE to Regex
I have a bit of code that converts a Sql Like expression to a regex expression for the purposes of a Linq to objects Like extension method. For some time I have been using this conversion.
This ...
6
votes
3answers
80 views
A regex in Java. Latin letters, digits, dots, and minus signs
There is a user login, and the requirements are the following:
The login must start with a Latin letter.
The login must finish with either a Latin letter or a digit.
There may also be digits, ...
1
vote
1answer
51 views
3
votes
3answers
52 views
Limited typecasting with regex
long time user/lurker at stackoverflow, first time here. I've seen a lot of questions like this have people point to this section of the StackExchange network so I hope this is the right place.
I'm ...
4
votes
1answer
90 views
Regex parser - request for review and optimization
The whole question is Better implementation of a simplified regular expression engine?.
I have solved the question, and in turn felt the need to get it reviewed. Any suggestions for clean up and ...
0
votes
2answers
81 views
Reducing number of blank spaces
This program takes blank spaces before some chars like > < />, and if there is more than one blank space in the line, it will reduce to one.
return source.replaceAll("\\s{2,}", " ...
5
votes
2answers
159 views
What do you think of my regex for URL validation?
I would like you to review my regex. It's suppose to recognize common URLs like:
http://www.google.com
http://www.sub1.sub2.google.com
https://www.google.com
http://www.google.com/path1/path2
...
1
vote
2answers
132 views
Performance: getting first value from comma delimited string
I've got a string that has values that are delimited by comma's, like so:
$var = '1,23,45,123,145,200';
I'd like to get just the first value, so what I do is create an array from it and get the ...
2
votes
1answer
80 views
How to replace plain URLs with links, in javascript? [closed]
I've nearly got this working. I wanted to know if there is a much better way. One problem is that no matter what there will be cases where a URL is incorrectly identified and as such the end result ...
3
votes
1answer
76 views
Optimize regex for maximum speed
According to http://stackoverflow.com/questions/19608546/optimize-regex-for-maximum-speed
and comments to ask my question here .
Please help me to optimize following regex to best performance . I have ...
1
vote
2answers
75 views
How do you “sordid sort” alphanumeric strings?
The question is about sorting alphanumeric string in a "more natural" order. Source: Marc LeBrun's "Sordid Sort" Computist Quiz
Often a system string comparison sorts alphanumeric data ...
1
vote
2answers
103 views
Trying to improve my javascript code in this simple challenge from coderbyte
Here is a slightly modified challenge from Coderbyte:
Determine if a given string is an acceptable. The str parameter will be composed of + and = symbols with several letters between them (ie. ...
1
vote
2answers
65 views
Checking name E-mail and unit-test
Please tell me what you think. Is my code bad?
Function checking
#-*- coding: utf-8 -*-
import re
import unittest
def email_check(mail): # E-mail as argument func
compil = re.compile(r"""
...
15
votes
4answers
1k views
Regex to parse semicolon-delimited fields is too slow
I have a file with just 3500 lines like these:
filecontent= "13P397;Fotostuff;t;IBM;IBM lalala 123|IBM lalala 1234;28.000 things;;IBMlalala123|IBMlalala1234"
Then I want to grab every line from the ...
3
votes
1answer
53 views
dir=“auto” JavaScript shim for IE
Reason for script:
dir="auto" is an attribute value from the HTML 5 spec with current poor support in IE and Opera browsers ...
2
votes
1answer
72 views
JavaScript HTTP regular expression
I am currently using the following to convert [url=][/url] to an HTML link:
s = message.replace(/\[url=([^\]]+)\]\s*(.*?)\s*\[\/url\]/gi, "<a href='$1'>$2</a>")
That work's fine.
I ...
-1
votes
1answer
47 views
Multiple of a number through a regular expression [closed]
How do I find if a string contains a number which is a multiple of 5 or not? Without converting/casting it to an integer?
1
vote
1answer
81 views
wild card pattern matching algorithm
i was trying to write code which does a validation for below wildcards:
'?' ------> The question mark indicates there is zero or one of the preceding
element. For example, colou?r matches ...
0
votes
1answer
39 views
Cleaner RegEx Syntax
I've got information that is imported from a CSV file that my site grabs every day with PHP. I'm just learning RegEx so I'm able to do what I need to do but am looking to get more efficient with my ...
1
vote
4answers
111 views
How can I shorten and remove repetition from this Python script?
I've got a CSV that contains users and permissions in the below format, where users can have as little as one or as many as eight different permissions:
...
1
vote
2answers
94 views
Optimization of a while-loop searching for words in a dictionary
This is my first question here. I'm using an open source program called MElt which lemmatize (give the lemma example:giving-->give) of words. MElt works on Linux and its programmed in Perl and ...
3
votes
1answer
221 views
Regex to remove inline javascript from string
I need to remove inline javascript for a given string. Examples:
If user typed: <img onload="something" />
I should need to convert into <img />
I created this PHP code and it ...
0
votes
1answer
78 views
Avoiding dynamic RegEx creation in JavaScript
This function's job is to replace several text smilies, e.g. :D, :), :love with the appropriate smiley image.
In my opinion my code has several issues, yet the main problem is that a lot of quite ...
1
vote
0answers
110 views
Regular Expression Generator [closed]
This library allows you to call functions to describe a regular expression, and then check if a string matches that regex- or replace things in a string based on that regex. I am trying to improve my ...
0
votes
3answers
59 views
Structured instructions for simple extraction script
I have a rather simple task in trying to extract keywords from input.dat which looks like:
func1
{
yes true;
keyword123 (1.1 0 -0.3);
gamma (0 1 0);
dir ...
2
votes
1answer
177 views
String Interpolation / Word Matching with XML in C#
I'm working on a project where I need to map XML values to field names. Classic CS problem, I think I've got a pretty good approach but would like feedback.
For example: breachReportType matches to ...
1
vote
1answer
402 views
string compare, sort, regex split
I am writing a simple code to accept/read a input of lines from a text file, split it into my class variables, sort them and finally display the input in the ordered form. But I am struggling past ...
4
votes
1answer
221 views
Faster code for SVG path parsing? Perhaps improved regex?
I have a module in Python for dealing with SVG paths. One of the problems with this is that the SVG spec is obsessed with saving characters to a pointless extent. As such, this path is valid:
...
3
votes
1answer
185 views
Trim certain characters from a string in javascript
I want to remove not only spaces, but certain characters aswell from the beginning or end of a javascript string.
function trim(str, characters) {
var c_array = characters.split('');
var ...
2
votes
2answers
116 views
Matching a pattern in many lines of text, Java?
This is the relevant piece of my code (false is returned if the whole cycle is finished, pattern is a String passed to the function):
for (FileLine fileLine : fileLines) {
itemText = ...
1
vote
1answer
58 views
Regular Expression in Javascript to test a string of 1s and 0s
I have a string of four bits which represent true/false values. There are only seven valid options:
1010
1110
0000
1101
1001
1000
0101
There are three options which could potentially be selected ...
2
votes
2answers
120 views
Should I be using Regex to uppercase uncommon characters?
I've written a function for converting strings to upper case. It currently works by replacing each character using a Regex pattern with a hash:
# Special upcase function that handles several ...
3
votes
1answer
125 views
Mathematical expression evaluator.
Code reviews and suggestions to improve coding style are welcome.
using ExpressionEvaluatorLibrary;
namespace ExpressionEvaluator
{
class Program
{
static void Main(string[] args)
{
...
2
votes
2answers
67 views
Trying to improve a working regex
I am extracting data from a text file. Some of the lines from which I want to extract the data consist of a text description with single spaces, followed by a multiple-space gap preceding four fields ...
0
votes
0answers
69 views
JavaScript regular expression literal as string literal [closed]
Please refer to this question for more discussion.
JavaScript string literal sometimes to many escaping slashes. The following address this problem by converting a regular expression literal into a ...
2
votes
1answer
115 views
Can I make a regex array to iterate through in C++?
I have to check a string to various regular expressions in C++. Up to now, I've done this using something similar to this:
regex regex_a (".."); string rewrite_a = "($1/$2)";
regex regex_b (".."); ...
2
votes
1answer
109 views
Regular expression for application version
Only these formats are accepted.
1.1.1
1.1.1-r
1.1.1-b
1.1.1-r1
1.1.1-b1
I wrote this code. What don't I like in it? I used parentheses and now I have two groups. In fact, I don't need to do ...
0
votes
1answer
71 views
Improvment of and looping in a regular expression pattern
My implemented regex pattern contains two repeating symbols: \d{2}\. and <p>(.*)</p>. I want to get rid of this repetition and asked myself if there is a way to loop in Python's regular ...
2
votes
1answer
1k views
Faster JavaScript fuzzy string matching function?
I'm using the following function to fuzzy match strings:
function fuzzy_match(str,pattern){
pattern = pattern.split("").reduce(function(a,b){ return a+".*"+b; });
return (new ...
1
vote
2answers
157 views
php most efficient way to check if a variable contains only certain chars
I have a small function which I regularly use to check if a variable contains only [a-z][0-9] and the special chars '-' and '_'. Currently I'm using the following:
function is_clean($string){
...
1
vote
1answer
69 views
To extract specific information in the stack trace using regular expression
I encountered a problem at http://regexone.com/example/6?
You can view the problem by clicking the link.
There was required a regular expression to extract the method name, filename and the line ...
1
vote
3answers
457 views
How should I read coordinates from a text file?
I have a text file with lines that look like this:
Robot(479.30432416307934|98.90610653676828)
Robot(186.42081184420528|213.11277688981409)
Robot(86.80794277768825|412.1359734884495)
or, more ...
2
votes
1answer
42 views
Encapsulate results in div tags
I would like to turn the following:
<div>this is a $test</div>
into
<div>this is a <div>$test</div></div>
currently I have
var regexp = new ...
1
vote
2answers
46 views
How to make this Regex more flexible?
I am creating a simple template engine that uses Regex to find special expressions, which are parsed and processed. They are enclosed in Ruby-style opening tags and have the format:
<% label ...
0
votes
0answers
74 views
Python pattern searching using re standard lib, str.find()
I'm trying to improve some code in order to get a better perfomance, I have to do a lot of pattern matching for little tags on medium large strings, for example:
import re
STR = ...
1
vote
3answers
760 views
Regex to get all image links - is this efficient?
I have some pretty basic Regex that scans the output of a HTML file (the whole document source) and attempts to extract all of the absolute links that look like images. Whether they are actually ...
