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Comment by dj_mc_merlin | Hacker News Reader

+1 for fish, the autocompletion alone makes it my daily driver. You can get the same in any reputable shell, but I like that it is designed into it from the ground up (the zsh autocompletion plugin brands itself as "fish-like").

It's also compatible-enough with POSIX for most purposes, and supported as an alternative for lots of software (venv comes to mind).

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One area where fish is excellent is IMO interactive shell scripting. No more case..esac and friends. Fish adopts a python-like syntax that makes it ridiculously easy to write loops fast in the terminal.

So I read this and thought "wow, indentation would be so stupid to manage in a terminal... even typing python into python's repl is brutal" but then I looked up the syntax for a for loop in fish and it is exactly the same as the syntax in bash except it uses the word "end" instead of "done" and doesn't have "do"... what am I missing?

It's an absolute godsend. Scripting in it feels really intuitive compared to POSIX shells. I find it such a shame that we probably won't get rid of POSIX shells for at least a couple more decades... if that.

Well, oilshell has been positioning itself as an upgrade path forward.

You can have real Python scripting with xonsh. It combines Python ness and shellness very nicely.

I agree that fish is a sweet middle ground spot.

How often do you find yourself forced to use bash? ssh/machine init scripts/etc. I could never use an alternative shell full time because I need to stay good at bash.

I've been using fish at home and bash at work for almost a decade now, and it's been fine — and because I'm at a fish shell on my own computer far more often than I'm at a bash shell on a work server, I'm willing to take the slight productivity hit there, because I gain overall.

The thing is, when I picked up fish, I couldn't forget my existing bash knowledge. I still have to write normal bash-dialect shell scripts, and with the fish syntax being so much nicer and simpler, the two can happily co-exist in my head. Occasionally I'll hit Up to search through history instead of Control-R, but I quickly realise what I've done and use the bash keybinding instead. And the only fish aliases I missed were 'l', 'll', and 'la', which I just manually copied over without bothering with the rest.

If I had to use bash more often at work... I'd still use fish at home after all the time I've sunk into it, but YMMV.

“I have to use the lowest-common-denominator thing everywhere because I have to use it somewhere“ is an argument that never made sense to me.

Switching between tools has a cost, so the tool needs to be not just better than another, but better after accounting for switch cost.

And the cost has to fit in to your budget. I'd rather spend my budget on learning emacs, for example, instead of spending it switching to a new shell.

It depends on your role. Many people regularly maintain or interact with prod deployments which cannot be customized to your liking. So it may be "somewhere" or occasional in your case but not in all cases. Switching back and forth between shell syntax every few hours is very disorienting and worse, can cause serious errors (for ex: if I have a local alias with rm="rm -i" but a prod server doesn't have it)

That's pretty much my argument for choosing Bash over Python for my everyday scripts. It's sensible.

This is a benefit of Oil, and part of the reason for it! I don't think having a hard "fork" between POSIX/bash and another shell is desirable.

So Oil is almost indistinguishable from bash at first, but you can unlock more powerful functionality with the var and proc keywords, etc.

This page has the old sh and new Oil idioms, but importantly Oil runs all the old stuff!

http://www.oilshell.org/release/latest/doc/idioms.html

POSIX compatibility would be enough to make oil a legitimate replacement shell for me but the bash compatibility makes it stand out as an alternative to take seriously.

Does oil allow a gradual upgrade path to using oil semantics for stuff like “echo $dontbreak”? Are there “set” options that enable oil semantics? Sort of like “use strict” in JavaScript and perl

Yes that's exactly how it works, with shell options!

http://www.oilshell.org/blog/2021/01/why-a-new-shell.html#ho...

I need to document things a bit better but the idea is here: https://lobste.rs/s/ritbgc/what_glue_lanugages_do_you_use_li...

In the case of echo, we respect -e and -n, but we also have "write -- -n" for correctness. I try not to "stomp" on existing names.

---

And yes there's an analogy to Perl: http://www.oilshell.org/blog/2020/07/blog-roadmap.html#the-u...

>I could never use an alternative shell full time because I need to stay good at bash.

Getting "good at bash" is a game with diminishing returns.

It's so random and non-orthogonal (bash itself, and the flags of common UNIX cli utils) as a scripting language, that you always end up having to look this or that, and with crazy corner cases you've missed.

not OP, but an avid fish user.

I switch to bash about once/month:

* for/while loops with a lot of logic that I don't feel would be worth translating to fish

* dealing with obscure/strange other things that again wouldn't be worth the time to translate to fish

ultimately, I feel that I get such benefit out of fish that the occasional switch to bash is worth the pain.

Ooh switching to Fish from Bash could be a nice weekend task. Any tips on common tripping points?

Do it! You will never look back.

The most common tripping points are the minor adjustments in syntax, probably the biggest one being command substitution:

Bash:

    $ echo “$(ls -al)”

Fish:

    $ echo (ls -al)

You get used to it though.

Another thing many bash-ers sometimes miss is the !! substitution, e.g.

    $ apt update
    # permission denied
    $ sudo !!

This doesn’t work in fish, BUT fish does offer a handy keybinding out of the box to prepend ‘sudo’ to your current command line (submitted by yours truly). So when using fish, you’d handle the above scenario like this:

    $ apt update
    # permission denied
    # press Up or Ctrl-P followed by Alt-s
    $ sudo apt update

There are so many other great things I love about fish, but this comment is already long enough.

Be sure to read (or at least scan) through the user guide on their website. It’s an easy read and not dense. You can also view it at any time by running `help` from inside fish.

I can’t recommend fish highly enough, I’m excited for your journey :)

Adding this to your config.fish will give you !! and !$ in fish

    function bind_bang
        switch (commandline -t)[-1]
            case "!"
                commandline -t $history[1]; commandline -f repaint
            case "*"
                commandline -i !
        end
    end

    function bind_dollar
        switch (commandline -t)[-1]
            case "!"
                commandline -t ""
                commandline -f history-token-search-backward
            case "*"
                commandline -i '$'
        end
    end

    function fish_user_key_bindings
        bind ! bind_bang
        bind '$' bind_dollar
    end

I’ve been a fish user forever, but the lack of support for sudo !! has never made sense to me. I’m glad to finally know that there’s a 2-keystroke alternative.

In regular Bash just press up and opt-up. If that doesn’t work your key bindings are bad and you should fix them. I never understood why anyone would ever use !! instead of something that is fewer key presses and more universal.

Another common thing I had to learn when I switched to fish, is the basic for-loop construct. Luckily it's super simple, here is an example:

   for f in (ls -1 *py); echo $f; end

One more thing to note is setting ENV var FOO to value bar is

   set -x FOO bar

Note no equal sign. To delete an ENV var use `set -e FOO`.

If you want to set ENV vars permanently for your login shell, the file to edit is `~/.config/fish/config.fish` and the syntax is:

   set -gx PATH  $PATH /some/new/path

which means set var PATH to whatever PATH contained before with /some/new/path appended to it.

I used fish for two years or so, and recently switched back to zsh, mainly because Fish is too slow to load, and this is not something the developers are willing to fix. The problem I had was that I needed to load a “bare” shell, without plugins or anything else, but this is not functionality fish provides, and judging from the developers’ comments something they are not going to.

So I spent a day migrating my fish config to zsh, and am much happier now.

This is interesting as I had the exact opposite experience. Fish is screaming fast for me compared to zsh, primarily because I don’t need to use any plugins to achieve all of the functionality that I needed to use many plugins to achieve in zsh. The totality of my fish config files, not including functions, is maybe a couple dozen lines [1].

Regarding a bare shell: perhaps I’m not understanding your exact needs, but fish is able to check whether or not it’s being used interactively with `status is-interactive`, so you could certainly try wrapping all of the plug-in loading machinery around a guard like this.

[1]: https://git.sr.ht/~gpanders/dotfiles/tree/master/item/.confi...

If you install oh-my-fish, you can just use this plugin for !! https://github.com/oh-my-fish/plugin-bang-bang

Thank you so much! HN at its best!

You might want bass (https://github.com/edc/bass) or replay.fish (https://github.com/jorgebucaran/replay.fish) if you need to run bash scripts that modify the shell. I personally use replay.fish (although I guess I haven't updated in a while since my version is still called "bax").

If you want a plug-in free solution, you can try the following:

    $ exec bash -c ‘source script.sh; exec fish’

This has some caveats and won’t work in all cases (both bass and replay.fish go into more detail), but this is what I use and it hasn’t failed me yet.

But why with arrow keys? I couldn't figure out how to remap to tab and gave up on fish.

In fish, tab does normal completion. Right-arrow accepts the current suggestion. You can use Ctrl-F instead of right-arrow (as usual for Emacs-inspired movement keys).

Edited to add: A suggestion is a complete command line based on the history. Completion looks at the disk for file names and the like, and only talks about the current "word".

> Right-arrow accepts the current suggestion.

If the '→' key is too far away from the home row for your liking, you can use Control-E instead, as long as you're at the end of the input buffer (it's the "go-to-end-of-buffer" command normally)

Thank you. I will definitely try again!

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