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Comment by hiisukun | Hacker News Reader

In a lot of terminals, Alt+. (or Option+. on Mac) will paste in the last argument of the previous command.

    $ mkdir hi
    $ cd <alt+.>

You can hit . several times to cycle through earlier final args.

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More precisely, this is not a feature of the terminals but of readline.

https://www.man7.org/linux/man-pages/man3/readline.3.html

All engineers working with the command line (even after 35 years) really, really should open and read

    man bash

and

    man readline

man 3 readline

to make sure you don't end up with something like urxvt-readline(1)

Wow, I did not know that!

I would have referred to this using !$, which is one of the Bourne shell history substitutions. Like

  $ mkdir awesome
  $ cd !$

(The "!" has the connotation "history" in the shell, while the "$" has the connotation "last", as in regular expressions.)

An advantage of the way you mentioned is that you could actually see the history item displayed on the command line before running the command!

I use !$ multiple times every day but you just helped me make the connection to try !^ for the first argument and I think I'm going to start using that as well. Thanks!

There is also "!!" for the entire prior command line. Someone elsewhere in this thread mentioned the usefulness of

  sudo !!

for "run the entire previous command under sudo".

Another example could be

  echo "!!" > myscript

for "save the previous command into the file myscript".

I also use cat `which !!` every once in a while

At least in zsh, there are also !:1 for the first argument, et cetera with the rest of natural numbers, and something like !:* for all the arguments without the command.

The generic form is !n:m for n-th last command line and m-th argument, with an omitted n being a shortcut for the last line.

Not sure if all of this works the same in bash.

I use zsh so this is also going in my toolbox. I think I've reached for !:* in the past and didn't know it so this is useful

History expansion originated in csh, and was never in the Bourne shell. Bash, certainly.

Thanks for the correction. I often recognize when bashisms are bashisms, but I didn't realize that was.

And if you don't want the last argument but the nth one, press Alt-n before Alt-. (n starts at 0, so Alt-0 Alt-. in the above situation would get you "mkdir").

There are several other ways to do this sort of thing too. See e.g. https://stackoverflow.com/questions/4009412/how-to-use-argum...

Holy shit, I have gone 35 years without ever learning this fact.

!! substitutes the last command:

  sudo !!

and

  cd -

takes you to the previous directory.

!$ substitutes the last command's arguments, if memory serves.

Or ^r to search through the command history (bash only?):

    $ grep blah *
    $ ^r
    (reverse-i-search)`g': grep blah *

This is far and above my most commonly used shell command

Then you can even superpowerboost the ^r by installing fzf! https://github.com/junegunn/fzf

This can be made much more powerful by McFly, I recommend: https://github.com/cantino/mcfly

or <esc> .

zsh has "take" to mkdir and cd to it. Something like take() { mkdir -p "$1" && cd "$1" }

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