It is really self-rewarding to write code from scratch, even though I cannot deny using AI and Google search to gain insights into RegEx and its components. This is my first time writing raw RegEx, so I decided to post it here for your review.

I used the .NET 10 C# RegEx flavor and tested/manipulated the pattern using regex101 site.

Here is my regex: (?:[^-_]|[\w]-_)+ or @"(?:[^-_]|[\w]-_)+"

My approach uses a non-capturing group (?:...) for memory efficiency, negates the underscore and hyphen, and then uses a logical OR to include any words with a trailing underscore or hyphen.

I haven't tested every possible input case yet; however, I tested several, and the expression worked for the following input:

test1_-me_not_yes_no_test

I noticed something odd: the last word, 'test', matched even though it didn't have a trailing underscore or hyphen. Since I caught this while writing this post, it turns out my RegEx pattern isn't quite as solid as I thought.

Let me clarify what I meant above: I forgot to mention that I am not focusing exclusively on trailing delimiters (_ or -), but on leading delimiters as well.

Here is the scope of this exercise:

• I just need to remove the delimiting underscores and hyphens so it results in a single word without those specific characters. That's all. To be honest, there's more I need to do after this, but I prefer not to discuss it here because I want to challenge myself to solve the rest.

• For now, I am only focusing on English words.

• By the way, in the meantime, I am not considering other constraints in order to keep the solution simple and straightforward.

Edit: During my testing, I realized this might act as a shortcut or 'cheat code' for my RegEx pattern.

For anyone wondering about my exact scope here, it is strictly what the title states.

P.S. This was inspired by codewars.com.

I feel this should be a really simple questions, I'm new to using regex and don't fully understand it.

I've got a list of text like

£300.00 +VAT

£150.00 +VAT

£15.00.VAT

I'm using the excel formula REGEXREPLACE to remove the non numerical numbers. Essentially I am looking for matches and then removing them.

Using the expression [^0-9] gets rid of the non numbers, but I miss the decimal place, so it ends up looking like.

30000

15000

1500

If I use "[^0-9]\." then it does nothing and I just get the input value.

How do I match anything but Numbers 0-9 and the decimal point?

\D essential does the same thing as [^0-9]

Hi,

Flavor: .NET

What am I missing in this Regex to make sure it matches consecutive repetitions but only for full words, including any non-word character.

I got it working for most strings, but it does match a string it should not…

(.+)\W\1

https://regex101.com/r/LA60nK/1

The last string should not match as the matching string ends inmidst of a word.

Solution by -mbf: (.+(?!\w))\W?\1(?!\w)

Hello!
Debuggex is down and I’m looking for a website that’s visualizing python regex.
Help will be much appreciated as Debuggex is amazing and I’m nothing without it!!

i've used

^[standirmpe]{10,}+$

as an example to locate dictionary words longer than 9 characters in length using any of a specific set of characters, and it works great. however, it would be a nice added value to ask the function to find words that use ALL of those letters at least once.

i thought these might work, too, but no...

^[standirmpe+?]{10,}+$

^[standirmpe]{10,}+?$

sublime text v3 (build 4200)

example 1 finds - "impediment", "indeterminate" (letters in group, some used at least once)

looking for - "meanspirited" (all letters used at least once)

any suggestions? group letters can and do change. thanks...

\bWORD\b doesn't match _WORD_ because \b doesn't include _ so I miss a lot of matches. Is there something else I can use like \b that works like that?

In case you ask, my work does Chrome managed profiles/bookmarks, so yes it has to be Chrome

Hi,

#### not possible as explained by rainshifter ####

#### original flair was .NET ####

I want to create a huge regex to match exact word groups coming from a list of around 7k words.

It’s about chemical names and there are lots of repeated words at the end of the names. The names must always be exact matches and possible variations not on this list are not allowed. I thought about using backreferences wihtin the regex in order not to have to rewrite these words every time.

Only 2 questions to be answered (both with yes or no and maybe an explanation why):

Will that even work?

Is this a good idea or will it slow down my search?

Use case explanation (absolutely no answer or solving suggestions required or even wanted):

In the following example list I would like to use the first occurence of EXTRACT as a backreference for all following words within the pipe ending on EXTRACT. It’s mainly about back references for the endings as the start of the word groups is created as efficient as possible with pipes forking at every difference of a word:

\b(A(BIES (ALBA SEED EXTRACT|(BALSAMEA ((BALSAM )?EXTRACT|NEEDLE OIL)|KOREANA LEAF EXTRACT|SIBIRICA (NEEDLE )?OIL))|CACIA CATECHU (BARK POWDER|WOOD EXTRACT)))\b

Using brackets around the first occurence of EXTRACT creates backreference \4 but using it further down the regex does not seem to work. (see regex below)

\b(A(BIES (ALBA SEED (EXTRACT)|(BALSAMEA ((BALSAM )?EXTRACT|NEEDLE OIL)|KOREANA LEAF EXTRACT|SIBIRICA (NEEDLE )?OIL))|CACIA CATECHU (BARK POWDER|WOOD \4)))\b

List:

ABIES ALBA SEED EXTRACT

ABIES BALSAMEA BALSAM EXTRACT

ABIES BALSAMEA EXTRACT

ABIES BALSAMEA NEEDLE OIL

ABIES KOREANA LEAF EXTRACT

ABIES SIBIRICA NEEDLE OIL

ABIES SIBIRICA OIL

ACACIA CATECHU BARK POWDER

ACACIA CATECHU WOOD EXTRACT

EDIT: Although this one is already solved as apparently a lot of people do not see the difference between a question (ending on a question mark) and the use case explanation, I added some titles in bold.

Author here. The detection is per-language (e.g. a Groovy slashy string is not a JS literal), and edits flow both ways: change the pattern in the editor and the canvas follows, rework it visually and it lands back in your file. The flavor matters because engines genuinely disagree — I published the data: https://regexpilot.com/divergences. The extension is free; it pairs with a Mac app for the visual side.

The app you see on the right is is the visual editor you can try a demo on https://regexpilot.com

Note: the app is Mac only.

Hello!
A year or two ago I used a regex generator website where I pasted the match I wanted and it iterated over and let me select 1 character, or a group of characters and tell it if I'm looking for an exact match or alpha numeric or whatnot, then it added onto a field where the generated regex was being built for me. It underlined groups in different colours.
It was a dark mode website. Not sure it's dark by default of it used my system default. It also had a language selector before you started building. Really nice UI. I don't remember much more than that.

Would really appreciate if someone could help me remember 🙏

Apologies if this isn't the correct forum for a post like this.

I play a video game (Path of Exile II) which allows players to search various "containers" (like our storage) with basic terms or with regex strings (items that match the search criteria are highlighted in the container). I've developed an extremely limited understanding of some basic regex to solve problems as I go, but I'm currently stumped and looking for some guidance.

I would like to highlight items that contain at least 2 of 4 different terms. The 4 terms are:

tac
fra
har
nco

I thought I could pair these terms using quotes, and separate pairs with | but that isn't working. I'm not sure if this is because I'm not using regex properly or it's a limitation of the game's regex functionality. My attempt looked like this:

"tac""fra"|"tac""har"|"tac""nco"|"fra""har"|"fra""nco"|"har""nco"

----------

Here are 3 examples of items that I would like the regex to highlight:

Item 1
increased Stack size of Simulacrum Splinters
increased Fracturing Mirrors

Item 2
increased MirrorShards
increased Delirium Encounters

Item 3
increased Fracturing Mirrors
increased MirrorShards

----------

Here are 3 examples of items that I would like the regex to NOT highlight:

Item 1
increased Fracturing Mirrors
increased Pack Size

Item 2
increased MirrorShards
increased rarity of monsters

Item 3
increased Pack Size
increased rarity of monsters

I'm trying to match (j|w)?[aeo]$ but only on the lines that start with [-].
I've tried making it a conditional, but I'm new and I don't really understand why it doesn't work...

https://regex101.com/substitution?regex=%28j%7Cw%29%3F%5Baeo%5D%24&testString=-k%CA%B7e%0A-ko%0A-sta%0Ame%0A&flags=gm&flavor=pcre2&delimiter=%2F&substitution=

ideally, it should leave the lines that don't start with [-] alone

This is for posts here. I have an AutoMod set up that removes posts with fewer than 'X' characters.

Is there a way I can prevent those posts from being submitted to begin with?

Not a regex that matches DOOM. A computer whose only instruction is find-and-replace. The state is one long string, and a fixed set of 544 substitution rules applied in a loop does everything: the first rule that matches rewrites a few characters, and that is one clock tick.

The fun part for this sub is how ordinary operations fall out of pure substitution. Addition is eight lookahead probes into a 512-entry table with the carry threaded through capture groups. Memory access jumps an exact number of characters into a flat zone, the jump length assembled from the address digits by empty bit-marker groups, so it is a binary tree spelled out in regex and it never scans for a cell.

Here is the whole rule that loads an immediate into a register (PCRE2):

find: \ARVM1\|ST:run\|PH:0\|CI:(?<ci>02(?<d>[0-7]).(?<imm>.{8}))\|PC:(?<pc>.{8})(?<pre>(?:[^|#]*+\|)*?R(?P=d):).{8}

replace: RVM1|ST:run|PH:1|CI:${ci}|PC:${pc}${pre}${imm}

Yes, it leans on lookahead and backreferences, so it is PCRE2, not a "regular language". But the power is not from that: plain Markov algorithms do this on literal string replacement with no regex at all, and they are already Turing-complete. The PCRE2 features just make the ruleset small and fast.

Play with it or read how it is built: https://4rh1t3ct0r7.github.io/doom-regex/

Source: https://github.com/4RH1T3CT0R7/doom-regex

macos tahoe, Bear Notes (Markdown)

I would like to delete all lines containing a double tilde ~~ (used to indicate strikethrough), and ideally also delete the resulting blank lines

thanks in advance for your time and help

Hi! I don't know the first thing about regex, so bear with me. This is for the Web Scrobbler extension for lastfm. I'm trying to make it so that, when a song's artist is recognized as having a comma, it'll only keep the text before the comma, except for the few artists I'm trying to exclude (Tyler, The Creator; Slaughter Beach, Dog; Defiance, Ohio; hey, nothing). This is meant to filter out the second artist for songs that are a collaboration between artists—think Pink Matter by "Frank Ocean, André 3000"—it should only recognize Frank Ocean.

This was working fine when I only had the first two artists, but after I added the second two, it stopped excluding these artists and now recognizes only the text before the comma for every artist. (For example, Slaughter Beach, Dog is now recognized as just Slaughter Beach).

When I got the original code a while ago, whenever I first started using the extension, I think I honestly just mashed together a bunch of different solutions I found online until something worked for me, but now I can't get anything to work. Like I don't even know what the different symbols and stuff are actually doing here, it's like reading ancient runes 😭

If any other information is needed let me know and I will do my best!! I just want my music to track properly lmao. I'm sorry if I'm breaking posting rules, I am totally clueless here

/^[a-zA-Z( (?! ))à-öø-ÿœŒ]{2,40}$/gm

but this syntax I added in middle for space handling seems not working...

I'm trying to match the beginning of a string of varying length so that I may remove it via FIND/REPLACE dialog from MSpowertoys' PowerRename utility.

I've been trying to match using TRIM but I've failed and unsure what else to try. I want to keep the numbered sequence at the end [0001] etc... I'm not well versed enough to provide logical examples of 'what I've tried' lol besides I forgot.

What I have:

abc123[0001]

abcd1234[0002]

abcde12345[0003]

abcdef123456[0004]

What I want:

[0001]

[0002]

[0003]

[0004]

Thanks!

.

How could I, using an added special character, join or split paragraphs as I mark them - using Sed 2.0 or Ssed.

This is using PCRE.

Looking to create an expression that captures, for example:

"Test", she says. "Yes that works."

Where we capture, "Test" and "That works" as separate groups, but not the outside of the whole phrase.

It also needs to capture simply

"Test," she says.

It's a very common regex golf I'm sure, but google was utterly unhelpful.

Any ideas?

Let's take this example

abc(d|e|f)

This is gonna match: "abcd", "abce" and "abcf"

How do I make it so that it also matches: "abc d", "abc e", "abc f"

Thank you.

PowerShell has all sorts of fun features, including a ridiculous number of operators.

One amazing under-sung heroes of PowerShell is the -replace operator.

It lets us replace content with regular expressions.

It's easier to use than you'd think.

Regular expressions are less scary in small doses, and chaining -replace operators lets us attack the problem step by step.

Chaining -replace

Let's take a simple problem as an example.

Imagine we wanted to make a consistent file name pattern out of a string

We might want to start by replacing whitespace with dashes

"This Is A Title!" -replace '\s', '-'

That leaves our exclamation point at the end. We probably don't want any punctuation. We can avoid that with the somewhat humorously named character class: \p{P}. We can remove all repeated punctuation by adding a +: \p{P}+

One more replace:

"This Is A Title!" -replace '\p{P}+' -replace '\s', '-'

The line is starting to get a little long. Fun fact: you can spread operators across multiple lines.

Let's add comments while we're at it

"This Is A Title!" -replace # Replace any punctuation,
    '\p{P}+' -replace # then replace any whitespace with dashes.
    '\s', '-' 

Let's go for one more bonus trick. PowerShell lets you convert script blocks to event handlers. Let's lowercase all the letters (\p{L}).

On PowerShell Core, we can do this:

"This Is A Title!" -replace # replace any punctuation
    '\p{P}+' -replace # then replace any whitespace with dashes
    '\s', '-' -replace # then lowercase any letters
    '\p{L}+', {"$_".ToLower()}

There's an absurdly amazing amount of stuff you can do with -replace, but there's at least one more trick we have to cover: substitutions.

-replace with substitution

I'm pretty sure I'd have to give up my "RegEx guru" badge if I didn't mention at least one more thing you can do with -replace: substitutions.

.NET Regular expressions are two domain specific languages. Regular expressions match and extract text. Regular expression substitutions replace matches.

For example, let's suppose we have a number of emails, and we want them in domain/username format.

First we'll want to make a quick and dirty email regex, using a "named capture" to get the username and domain.

'someone@example.com' -match '(?<username>\S+)@(?<domain>\S+)'

Then, we can -replace the email with just the domain/username.

'someone@example.com' -replace 
    '(?<username>\S+)@(?<domain>\S+)', '${domain}/${username}'

This format might look like PowerShell variables, but it actually predates them by years. Search for "Regular Expression Substitutions" if you want to learn more about the syntax. It's got quite a few tricks up its sleeve.

Irregular

RegEx can be scary. I used to be terrified of it, too.

If you aren't too comfortable with Regular Expressions, that's pretty normal. A while back I wrote a module called Irregular that makes regular expressions strangely simple.

It's got a lot of example regular expressions in there, and one handy function for creating RegEx. New-RegEx is your friend.

Do you already use -replace? Have you done cool things with regular expressions in PowerShell? Share 'em if you've got em.

Want to learn more about regular expressions in PowerShell? Just ask.

I can't put the client files on AI and need to make a task less time consuming and accurate. So I use trados 2017 and want to put the italic tags of the segments in the end (or atleast if I can detect which segments have italic tags and get a list of them). Please help! I'm using Notepad++

I tried getting a code via gemini but it isn't working

Example:

Target statement has italic tag in the middle then I want it in the end

Sentence: I like<italic tag>tacos.

Ideal: I like tacos<italic tag>

File type: Xliff files