[TUHS] Command Line Editing in the Terminal Driver (Was: A few comments on porting the Bourne shell)

On Fri, Dec 30, 2022, at 12:42, Sven Mascheck wrote: This phrase has haunted me for years. It’s so clearly the “correct” separation of concerns, until you actually attempt implementing it. And Bourne’s irregular grammar certainly doesn’t help here. I’d prefer to move beyond readline, ideally something like text objects per vim/zsh/treesitter. But having one parser in the interpreter and another in the line editor becomes quite exciting if you want a true bourne or even posix sh. But the thing that brought be back to playing against this quote again this year was starting to research the QED lineage and discovering helix & kakoune. Honestly, they feels like the most coherent advancements in QED-style editors since sam & acme. (Yes, I’m irrationally excluding vim text-objects, mostly because no one removed editor features that t-o made redundant. It’s as if ed had twice as many commands, one for regexp matches and one for pre-ken-QEDist exact matches.) Anyway, the only time I’ve really seen “line editing […] move into the terminal driver” sound possible was acme’s win. For those who haven’t had the pleasure, rsc describes it at 15:25 in https://research.swtch.com/acme. “I worked for many years in a shell without history or command line editing, and I never missed it because Acme is providing this for me.” It’s hard to convey how surprisingly pleasant sh or rc can be within acme win to someone who has only used them within a mere terminal-emulator-emulator. Especially since a greenfield terminal app has more code emulating old xterm behaviors than physical vt100 behaviours. This is especially exhausting when you try to use something like NeoVim’s :term expecting it to just work and discover that buffer-line-wrapping on window-resize hasn’t been implemented. Anyone seen any other “terminal drivers” that provide a pleasant alternative to line editing? -- ~j