alt Hacker Newssigh The usability of ! versus Ctrl+R in a shell is pretty much the same as the usability of ed versus vi, or moving files around using cp/mv versus using Midnight Commander or the like: in the first case, you have to accurately remember the past (which for many people is pretty difficult); in the second case, you don't have to, because you always have an immediate view of the state of the system and the preview of the effect you're about to incur.
And yeah, I've done editing with ed; it definitely beats "cat >file.txt" and copying parts around with head/tail and retyping the corrections manually, sure, and it works in every environment that can take line-oriented input from the user (so, literally everywhere), but that's about as much praise as I can give it.
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> in the first case, you have to accurately remember the past
Right, as a matter of (relatively trivial) cybernetics between man and machine, it rests on the weaker parts of the human.
TBF, it'd make a lot more sense if every command on screen (or given the timescale perhaps teletype paper prinout) was already labeled with the necessary number.
> you have to accurately remember the past
From personal experience I rarely reach for event-designators beyond the current viewport of the terminal. Referring to a command beyond that is, as you very much correctly point out, an easy way to get behavior you don't want. However, if you are always referring to things that are near-memory or even still directly visible in your terminal buffer — the gun-to-foot ratio becomes manageable. I use many (many) of these daily without issues, but it does require some additional discipline.
Also, and this I find important to note, `!!` and `!$` sit outside of the memory argument as they always refer to the last command and last-command's last-argument respectively — as such there shouldn't be any recall related problems (unless you are context switching and come back to a shell in a state you don't remember).
A common occurrence when my posts acquire attention is that I retroactively realize that some things could have been conveyed better; I read every comment and yours is a blessing in disguise to improve future writing.
Thanks for reading the article, and thanks for indirectly making me a better writer!
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EDIT:
by the way, for what it's worth, the below linked section describes how to effectively explicitly confirm what you would run as a safety measure if unsure:
https://refp.se/articles/your-shell-and-the-lazy-exclamation...