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https://buttondown.email/hillelwayne/archive/why-do-regexes-use-and-as-line-anchors/
Last week I fell into a bit of a rabbit hole: why do regular expressions use $ and ^ as line anchors?1
This talk brings up that they first appeared in Ken Thompson's port of the QED text editor. In his manual he writes: b) "^" is a regular expression which matches character at the beginning of a line.
c) "$" is a regular expression which matches character before the character (usually at the end of a line)
QED was the precursor to ed, which was instrumental in popularizing regexes, so a lot of its design choices stuck.
Okay, but then why did Ken Thompson choose those characters?
This discussion was created by janrinok (52) for logged-in users only, but now has been archived.
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Why Do Regexes Use `$` and `^` as Line Anchors?
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(Score: 5, Insightful) by WizardFusion on Wednesday March 27 2024, @10:34PM (23 children)
Why to websites insist on just using the middle third of the screen with massive amounts or white-space either side.
It's not like I am using a wide screen either, just standard 1080p laptop.
(Score: 5, Informative) by Rosco P. Coltrane on Wednesday March 27 2024, @10:40PM (18 children)
It's formatted for cellphone reading.
People browse on cellphones nowadays, and websites do this sort of garbage rather than write article with text that reflows gracefully, because whatever pile of Javascript powers their website lets them impose portrait mode on everybody, and it's quicker and lazier to ensure their content displays well when it's rendered only in one mode.
(Score: 4, Insightful) by janrinok on Wednesday March 27 2024, @11:27PM (13 children)
We sometimes get complaints from those who browse our site using smartphones etc. Why don't we use Bootstrap? they ask - which is what most sites optimised for smartphones use. We like our quirky olde-worlde appearance.
I am not interested in knowing who people are or where they live. My interest starts and stops at our servers.
(Score: 5, Insightful) by Rosco P. Coltrane on Wednesday March 27 2024, @11:41PM
Well, if you try modern here, you're gonna fail miserably 🙂
SN and /. are living internet history. They SHOULD look like the '90s, and if you try to modernize them, you'll lose what makes them what they are, and the audience that comes here to get their dose of the 90s. /. tried it and failed, and now they're more or less back to their old self and chugging along, doing what SN and /. do best; providing a taste of what the free internet was like a quarter century ago.
I want my mobile browser to render SN as my desktop browser does. It wouldn't be right if it tried to have a mobile version.
(Score: 4, Insightful) by krishnoid on Wednesday March 27 2024, @11:56PM (10 children)
How about a few CSS files, maybe even manually selectable -- phone, tablet, desktop? Then we don't need Javascript, and CSS is really powerful as it is.
(Score: 5, Touché) by janrinok on Wednesday March 27 2024, @11:59PM (3 children)
Are you volunteering for a job? :D
I am not interested in knowing who people are or where they live. My interest starts and stops at our servers.
(Score: 2, Interesting) by shrewdsheep on Thursday March 28 2024, @10:11AM (2 children)
Why the quip? The thread earlier was lining up against any change to the website. In view of the future of the site, I strongly support CSS optimizations and the use of limited javascript to improve usability. The old style can and should always be retained as a tribute to the legacy of the site. The user base has to be broadened for long term survival of SN and I believe that appearance and usability is a good part of it when it comes to attract new readership.
(Score: 4, Informative) by janrinok on Thursday March 28 2024, @10:54AM (1 child)
It was merely asking who would be doing this task? To have selectable CSS pages will require significant Perl code changes and new fields adding to the database so that the user's choice is remembered between log-ins. The displays are created by templates which might have to be changed to cope with different CSS. It is not my area.
No offence was intended. I did include a grin!
I am not interested in knowing who people are or where they live. My interest starts and stops at our servers.
(Score: 2, Interesting) by Anonymous Coward on Thursday March 28 2024, @04:42PM
User-selectable alternate stylesheets were an original design feature of CSS but it's unfortunate that the browser support today is completely useless.
The CSS2 specification actually says that user agents must provide an interface to change between alternate stylesheets [w3.org]. I don't know if this requirement persists in current specifications. Firefox has the choice in a hidden menu but it forgets your selection as soon as you reload the page or follow any link so it's basically unusable. Such a shame.
(Score: 3, Interesting) by bzipitidoo on Thursday March 28 2024, @12:24PM (5 children)
CSS is great, but should even that be necessary? Reflowing of text to fit window sizes is a core feature of plain old HTML. No more reliance on CR/LF for that. If a user is forced to scroll back and forth to view the full width, despite the site not using any JavaScript or set widths or whatever, that seems to me a problem with their environment, not the site. Note also that the browser has the final say over fonts. A site can give relative size differences; the user's system ultimately sets what size "big", "normal" and "small" are.
A common idea is a mobile version of the site. m.soylentnews.org
(Score: 3, Informative) by janrinok on Thursday March 28 2024, @12:50PM
I am not interested in knowing who people are or where they live. My interest starts and stops at our servers.
(Score: 2) by owl on Thursday March 28 2024, @07:29PM (1 child)
Because by far too many designers feel some hugely irrational need to control the layout to a level far more strict than "let html lay out the data based upon the viewport width".
Note that most of these designers are those from the "publishing" environment where positioning text in this corner of a page, and a highlight image over in this other spot, in order to leave room in three other places for three ad slots, was what they were trained to do.
I.e., they never even consider just letting the HTML lay itself out natively. They need to control where it goes, to the pixel, or they feel they have failed.
(Score: 2) by krishnoid on Thursday March 28 2024, @09:21PM
Designers are probably trained for traditional print media, and something that describes layouts and floats using declarative and markup languages is probably going to require a GUI for them to be able to do their thing. They're not coders, after all.
(Score: 3, Insightful) by maxwell demon on Friday March 29 2024, @07:39AM (1 child)
That's the absolute worst thing to do. If I follow a link, it should work equally well if I follow it on a desktop or on a laptop.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by maxwell demon on Friday March 29 2024, @07:41AM
Err, mistyped, and only noticed after submit: I of course meant desktop or phone.
And in addition I now have to wait with posting this correction due to the unreasonable long wait time enforced by the Rehash software.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Interesting) by Tork on Thursday March 28 2024, @12:23AM
Again I wasn't intending to raise this issue, I don't think it really needs to be fixed, it just became on-topic today. On a side note I do appreciate that the font shrinks as you go down the branch. Reading through threads works pretty well. It's one of the reasons I go here first before the green site.
🏳️🌈 Proud Ally 🏳️🌈
(Score: 2) by stormreaver on Thursday March 28 2024, @12:54AM (3 children)
Three-column layouts, where the main content is in the center, were common well before cellphones became widespread. That layout is common because there is a point where horizontal reading becomes less pleasant than vertical reading.
(Score: 3, Informative) by aafcac on Thursday March 28 2024, @02:18AM (2 children)
Yes, also remember that Xerox had their monitors in portrait format back when they were developing their paperless offices for a reason.
It's also worth recognizing that in some places that format of multiple columns makes it easier to fold up to not interfere with other folks on the bus while reading the newspaper.
(Score: 2) by krishnoid on Thursday March 28 2024, @09:27PM (1 child)
And the qwerty keyboard layout is designed to keep the hammers from jamming [dvzine.org].
(Score: 2) by aafcac on Friday March 29 2024, @02:14PM
Yes, and unfortunately one of those two things can be easily remedied as needed. It's one of the reasons why it's worth having a good monitor stand, it should allow you to rotate the screen 90 degrees if you're doing something that benefits from that. Or, just have the window manager tile the window to only take up half of the width.
The keyboard though is a much more annoying problem. Yes, you an use whatever map you like, so long as you have enough keys, but it's a whole thing to learn a new layout and if you're a decent typist it may not even be worth the effort.
(Score: 2) by krishnoid on Wednesday March 27 2024, @11:54PM
And why is there so much vertical whitespace when laptops are landscape-aspect-ratio, and small fonts? Oh, probably same reason.
(Score: 1) by zdammit on Thursday March 28 2024, @08:10AM (2 children)
I don't know about you but I find very wide text layouts hard to read and I like the sites that try to make it less wide. There is a typographic convention that says line width should be 2.x alphabets (x depends on who you ask).
(Score: 2) by VLM on Thursday March 28 2024, @04:40PM
It's been a battle for decades now, that source code should either be like literature or prose with short lines for the casual reader vs source code should be like a math formula where stretching one unitary concept into unneeded extra steps or extra lines is mere obfuscation to be avoided for the simplicity of one line for one concept.
(Score: 3, Touché) by owl on Thursday March 28 2024, @07:31PM
Then narrow your viewing window, and suddenly, you get "less wide" text layouts.
The only reason you get very wide layouts is you have your browser window sized to be "very wide". I.e., the problem is completely under your control.