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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) "$" is a regular expression which matches character before the character (usually at the end of a line)
QED was the precursor to ed, which was instrumental in popularizing regexes, so a lot of its design choices stuck.
Okay, but then why did Ken Thompson choose those characters?
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Why Do Regexes Use `$` and `^` as Line Anchors?
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Keep emotionally active. Cater to your favorite neurosis.
(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.