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The true power of regular expressions (2012)

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Re: The true power of regular expressions (2012)

#31

Post by ogogmad »

bryanrasmussen wrote: post #26
AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

there is, I think, a divide between programmers that is pretty basic. Do they need a language that maps somewhat to written human language, or can they adapt to languages that do do not at all resemble the human languages they are familiar with. This divide is most probably cultural, programmers in Western societies often have pre-programming familiarity with English and thus they do not need to learn a language that…

Slightly tangential to your point, but I'm leaning towards programming languages no longer limiting themselves to ASCII. IOW, I'm leaning more towards APL than to J. I'm wondering how much of a blocker it's been to not embrace non-ASCII characters, or italic/bold/underlined formatting.

Re: The true power of regular expressions (2012)

#32

Post by benj111 »

bryanrasmussen wrote: post #26
AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

there is, I think, a divide between programmers that is pretty basic. Do they need a language that maps somewhat to written human language, or can they adapt to languages that do do not at all resemble the human languages they are familiar with. This divide is most probably cultural, programmers in Western societies often have pre-programming familiarity with English and thus they do not need to learn a language that…

I think there's also a bit of Unix philosophy in there.

If you're using 5 different dsls to write a script, 1 more isn't really an issue. Now the fashion is for 1 big batteries included language, which requires you to know a lot of things itself, so that non regular (ha) DSL sticks out.

Theres probably an issue of many tools being much more powerful than the average case, so if you want you can write a re/bash/sed script that's impenetrable to the average programmer.

I don't know if the same is true for large individual languages? Could you take one element of c++ to the extreme to the point that it doesn't make sense to most c++ers?

Re: The true power of regular expressions (2012)

#34

Post by benj111 »

ogogmad wrote: post #31
bryanrasmussen wrote: post #26

Earlier quoted context omitted.

there is, I think, a divide between programmers that is pretty basic. Do they need a language that maps somewhat to written human language, or can they adapt to languages that do do not at all resemble the human languages they are familiar with. This divide is most probably cultural, programmers in Western societies often have pre-programming familiarity with English and thus they do not need to learn a language that…

Slightly tangential to your point, but I'm leaning towards programming languages no longer limiting themselves to ASCII. IOW, I'm leaning more towards APL than to J. I'm wondering how much of a blocker it's been to not embrace non-ASCII characters, or italic/bold/underlined formatting.

Problem is, how do you tell that character X is indeed character X and not something that looks like character X?

Further, how far do we take the function names are a language thing? Should an ss be rendered differently in Germany? Is leß() the same as less()?

So yes I don't mind non ASCII characters, I'm not sure this should primarily be about supporting users of foreign languages, rather to increase the number of characters.

Although at this point, I would guess that most programmers have some kind of ASCII compatible keyboard? So what's being gained by having characters that aren't on that keyboard?

Re: The true power of regular expressions (2012)

#35

Post by tcp_handshaker »

AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

>> I've always been wary of regexes.

Be afraid: https://owasp.org/www-community/attacks/Regular_expression_D...

https://en.wikipedia.org/wiki/ReDoS

Re: The true power of regular expressions (2012)

#36

Post by pygy_ »

AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

This is by design, the regexp syntax has been invented for write-only programming at the CLI, and graduated to ubiguitous programming language syntax because worse is better.

The regular formalism is all about composability, and most languages don't offer a way to compose regexps, which is a real shame IMO.

Re: The true power of regular expressions (2012)

#38

Post by actionfromafar »

bryanrasmussen wrote: post #26
AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

there is, I think, a divide between programmers that is pretty basic. Do they need a language that maps somewhat to written human language, or can they adapt to languages that do do not at all resemble the human languages they are familiar with. This divide is most probably cultural, programmers in Western societies often have pre-programming familiarity with English and thus they do not need to learn a language that…

I never have patience with normal regex but I can handle it when expressed something like this:

https://github.com/philiprehberger/dotnet-regex-builder

Re: The true power of regular expressions (2012)

#39

Post by ddevnyc »

AussieWog93 wrote: post #12

It might just be a me problem, but I've always been wary of regexes. They're not too bad to write, but reading them back and understanding what's actually going on can get a bit hairy. Plus, all of the subtle differences between regex libraries seems like a bit of a footgun. Obviously they have their place, but I know a lot of the older guys seemed to love them way more than the young.

I know I am very very alone in this, but I've always found regex very readable. It's just not _quickly_ readable. You can't look at 20 characters of regex and read it and understand it as quickly as you would 20 characters of English. The biggest issue, I think, is people trying to do that. Regex is very information dense, it should be approached with the care of a mathematical formula or a sudoku rather than English prose.
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