How do you feel about regex?

#regex #discuss

Regex seems to have a broad array of love and hate. How do you feel about it? Do you seek to use or avoid it as a problem solver, and how much do you understand it?

Latest comments (65)

Lewis Cowles • Jan 11 '22

It's generated code, according to a declarative syntax, that has been tested and iterated on by millions of projects over decades... What isn't to love?

Prefer if we can use simpler things, but if it's needed. Then it is needed.

Sérgio Araújo • Jan 10 '22

As a vim/nvim user I would say that regex is my bread and butter. I also love using GNU grep, "Global REgular exPression Print", sed and a bunch of other programs that make use of it.

joao-gouveia • Jan 10 '22

Regex is difficult to read and can have unanticipated side effects. I tend to run from it if I can.

George Johnson • Jan 10 '22

Very useful BUT it's almost an entire language in it's own right. I kind of respect that and just skirt around it. I use online regex builders when I need a regex for a filter style func call and that's me and regex done with until next time!

There was an 300 page O'Reilly book sold at one point just on Regex and nothing else! That's how deep the rabbit hole goes on regex. If you can avoid regex, then do so, if you can't then make the expression simple and watertight by testing the heck out it. Regex is greedy and if you don't test it properly you will regret it later.

MICHAELKITH (GitHub username) • Jan 9 '22

Hello Developers

lepinekong • Jan 9 '22 • Edited

In the past I hate them and just searched copy and paste because it was pretty simple need but as I'm currently developping a Visual Meta Programming tool I'm obliged to really understand what I'm doing like Lookaround and Lookbehind so I'm now starting to like them more :)

zakwillis • Jan 7 '22

I think they are great. They don't work in all situations.

ultrapico.com/expresso.htm is for .Net and a great tool for creating regex expressions, it doesn't support all elements of regex. Am not a super genius on them but they are an essential element of development for me when handling information.

Here is an example of configuration from a translation file from my application which is an awesome DevOps Deployment application am hoping to market in future.

The configuration below is to either find a value or a regex expression in an input file (typically itself an application configuration file) to clean a development configuration file. Sounds complex, but a great way of translating source configuration into something generic for different environmental deployment.

Regexes provides more control, but aren't always the best approach.

inforhino.co.uk/beta/automation-an...

                        {"IsRegex": false, "FindValue" : "C:\\\\InfoRhino\\\\cms\\\\IRWebsite\\\\IRWebsiteCMS\\\\wwwroot\\\\ClientConfiguration\\\\TConfigType.json", "ReplacementValue" : "{TargetServerRoot}\\\\ClientConfiguration\\\\TConfigType.json"}
                        ,
                        {"IsRegex": false, "FindValue" : "C:\\\\InfoRhino\\\\cms\\\\Adverts", "ReplacementValue" : "{TargetServerRoot}\\\\Store\\\\Adverts"}
                        ,
                        {"IsRegex": false, "FindValue" : "C:\\\\InfoRhino\\\\cms\\\\IRWebsite\\\\IRWebsiteCMS\\\\wwwroot", "ReplacementValue" : "{TargetServerRoot}\\\\wwwroot"}
                        ,
                        {"IsRegex": false, "FindValue" : "content\\\\Cards", "ReplacementValue" : "Cards"}
                        ,
                        {"IsRegex": true, "FindValue" : "(?is-nx:(?<=\"CardDomainHeaderCaption\"\\:(\\s{0,1})\")([a-z0-9\\s\\,\\.]+))", "ReplacementValue" : "{CardDomainHeaderCaption}"}
                        ,
                        {"IsRegex": true, "FindValue" : "(?is-nx:(?<=\"CardDescription\"\\:(\\s{0,1})\")([a-z0-9\\s\\,\\.]+))", "ReplacementValue" : "{CardDescription}"}
                        ,                       
                        {"IsRegex": true, "FindValue" : "(?is-nx:(?<=\"CompanyName\"\\:(\\s{0,1})\")([a-z0-9\\s\\,\\.]+))", "ReplacementValue" : "{CompanyName}"}