Regular expression as Finite-state machine - Short

A short introduction to regular expressions and how you can visualise them. It's very helpful when auditing input validation.

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[LiveOverflow]

Decided to make some shorter videos to cover a single isolated topic, because I worry that a lot of smaller tips like these are hidden in longer obscure videos of mine.

[ln]

Definitely a perfect quality-length video(like always), really good job.

[cyancoyote]

Amazing explanation! I'm sure this will help a lot of people! :) Will you be covering the latest CPU bugs, Spectre and Meltdown too? I think there's a lot of misinformation circling around the web on this topic.

[Zzznmop]

Excellent job at simply explaining another topic that gives mild anxiety at first sight.

[hanneshertach]

Funny you uploaded this now... I'm currently doing a programming exercise for uni where we parse regexes into finite state automata to check strings!

[Miskerest]

Maybe make a part 2 video about NFAs/DFAs. While this is a more in-depth CS concept not directly related to security, most people learning CS will encounter the terms. Maybe even go over how to implement Kleene stars, OR operators, etc in finite automate.

[Gameboygenius]

Do you have videos on Meltdown and Spectre planned?

[Arthur-qvnp]

Yay ! Now we can match a regular expression with a regular expression :p !

[irronwolf]

Personally, I use Regexr. It's a cool tool too

[ndm]

I'll have to give Debugex a try sometime. It looks really cool, and I like the visualization. I usually use regex101, just because I haven't needed anything better.

[tzokke]

I cant fucking believe that a 2 minute long video managed to explain regex better than 4 fucking years of IT education! Just more proof I pretty much wasted the last 4 years of my fucking life!

[shirshzibbu]

fun fact: regexps rule diagrams are called "railroad diagrams"

[Flarel]

I'm not 100% sure on this but can't we write regexs for programs that recognise things that aren't regular languages? Using more advanced features like backreferences and lookaheads and stuff? I just remember when being taught regular expressions in uni that there was a distinction between the formal languages regular expressions and the kind of regular expressions you might write in a program (although they do have a lot in common, as the ones we would typically write in a program are based off the formal languages/mathematical regular expressions )

[raular]

Hi, I discovered your channel some hours ago and found that there are lots of technical things you say.
Do you hqve any videos with the basics of some of this ones?
Or is there any topic you would recomend me to learn about?
*You can choose whatever subject of your own as long as you think it has helped you in some way.
Btw I'm in 1st year of computer engenyering.

[she_left_me]

upload video about meltdown and spectre vulnerability plz :D

[Yaxqb]

I use Regexr instead, the sleekest of the bunch imo. I don't know, I find these state debuggers harder to comprehend than a simple tooltip, that tells what each character does when you're hovering it. But that's me. :)

[xandercage]

@LiveOverflow.. Hey mate..love your channel and have watched all your videos. I just have some quick questions. I see that you love doing source code analysis, could you tell me some pdfs or websites which covers it from beginner to advance level. On the same note I am also interested in Computer Architecture Security from a hackers perspective. Maybe I dnt have the right word for it but i wanna learn how to make a network and the whole architecture secure. Thanks in advance. :) Love your channel

[orad]

Noooo it's my discrete structures II class all over agaib

[palmenros]

Even that it is not about this video's topic, I have a question, because there is a lot of desinformation out there. Is the Meltdown vulnerability a specific instance of the Spectre vulnerability? If not, why? Thanks

[ExEBoss]

Well, I generally write really complex regexes from the top of my head and get them right 99.9% of the time.