Debian’s apt-get and related tools are pretty fantastic. The command_not_found_handle tells you the package to install if the command you’re trying to run is not found.

> pacman
The program 'pacman' is currently not installed. You can install it by typing:
sudo apt-get install pacman
> # okay, fine, let me type or copy/paste that
> sudo apt-get install pacman

I don’t want that message to have an interactive prompt at the end (“Go ahead and install it? (y/n):”) but I do want a quick way of doing what it says. The computer just told me exactly what needs to be typed, so why do I need to type it myself?

This alias reruns your last command, grabs the last line from the error message, and runs it.

alias doit='$($(history -p \!\!) 2>&1 | tail -n1)'
> pacman
The program 'pacman' is currently not installed. You can install it by typing:
sudo apt-get install pacman
> # I've been expecting you
> doit
Reading package lists... Done
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