← Back to context

Comment by jakkos

2 days ago

Have you seen nushell? It lets me one-liner so many things that would have previously taken breaking out a "real" language to do

Contrived example:

  ls | where type == 'file' | sort-by size | take 4  | each {|f| {n: $f.name, s: ($f.size | format filesize MB) }} | to json

outputs

  {
    "n": "clippy.toml",
    "s": "0.000001 MB"
  },
  {
    "n": "README.md",
    "s": "0.000009 MB"
  },
  {
    "n": "rustfmt.toml",
    "s": "0.000052 MB"
  },
  {
    "n": "typos.toml",
    "s": "0.00009 MB"
  }

28 comments

jakkos

Reply
vidarh  2 days ago

With this:

    E = Struct.new(:name, :size, :type)
    def ls = Dir.children('.').map{ s=File::Stat.new(_1); E.new(_1, s.size, s.file? ? 'file' : 'dir') }

This becomes valid Ruby:

    ls.find_all{_1.type == 'file'}.sort_by(&:size).take(4).map{ {n: _1.name, s: _1.size } }.each { puts JSON.pretty_generate(_1) }

(drops your size formatting, so not strictly equivalent)

Which isn't meant to "compete" - nushell looks nice -, but to show that the lower-threshold option for those of us who don't want to switch shells is to throw together a few helpers in a language... (you can get much closer to your example with another helper or two and a few more "evil" abuses of Ruby's darker corners, but I'm not sure it'd be worth it; I might a wrapper for the above in my bin/ though)

0x3444ac53  2 days ago

I've tried nushell and other shell replacements and it just feels like I'm learning a new programming language for no good reason

  • ectospheno  2 days ago

    To be fair the example above is easier to remember than:

      ls -l --sort=size | head -n 5 | tail -n 4 | awk '{print $5 " = " $9}' | numfmt --to iec | jq --raw-input --null-input 'inputs | gsub("\r$"; "") | split(" = "; "") | select(length == 2) | {"s": (.[0]), "n": .[1]}'

    • fainpul  2 days ago

      This example shows nicely how ugly text processing is: you have to use head and tail simply to trim out the first line of ls (the total).

      I think it doesn't even work correctly. ls lists files and directories and then picks the first 4 (it should only select files).

      And this also uses awk and jq, which are not just simple "one purpose" tools, but pretty much complete programming languages. jq is not even part of most standard installations, it has to be installed first.

      7 replies →

  • bbkane  2 days ago

    Yeah... https://www.sophiajt.com/case-for-nushell/ makes a really good case for Nushell as an alternative to Bash.

    Unfortunately, I don't think Nushell brings much benefit for folks who already know Bash enough to change directories and launch executables and who already know Python enough to use more complicated data structures/control flow/IDE features

    I'm still rooting for Nushell as I think its a really cool idea.

    • misir  2 days ago

      For me the blocker was having to switch to bash/powershell when moving to a different machine (ie: servers, work machine, etc..). I would end up needing to redo same things to be compatible with the existing tools; eventually I just gave up and got used to readily available shells instead.

  • fainpul  2 days ago

    Ok if it's not for you. But there is of course a very good reason — work with objects in the pipeline instead of "dumb text". Also PowerShell and nushell are quite nice to learn, whereas Bash is absolutely horrible.

    • kelnos  1 day ago

      I wonder if this is a case of "worse is better", or just the long-term entrenchment of text. Because nushell hasn't been adopted all that much compared to bash or even zsh (or a "real" scripting language like python or ruby). I don't know much about PowerShell adoption (haven't used Windows in over 20 years), but I'd assume since it's a first-party system that's default installed(?), it's done better adoption-wise.

      I agree that bash sucks, but I really have no motivation to learn something like nushell. I can get by with bash for simpler things, and when I get frustrated with bash, I switch to python, which is default-available everywhere I personally need it to be.

      Back to text, though... I'm honestly not sure objects are strictly better than dumb text. Objects means higher cognitive overhead; text is... well, text. You can see it right there in front of you, count lines and characters, see its delimiters and structure, and come up with code to manipulate it. And, again, if I need objects, I have python.

      1 reply →

  • IshKebab  2 days ago

    Well, the reason is you can stop using Bash. If you never write Bash scripts already then you probably don't need it (and also congratulations on doing things right), but most people at least have lazy colleagues that write shell scripts. One day I'd like them to be not awful.

fainpul  2 days ago

In PowerShell:

  gci -file | sort-object size | select name, size -first 4 | % { $_.size /= 1MB; $_ } | ConvertTo-Json

  • xigoi  1 day ago

    ConvertTo-Json? What kind of naming convention is that, especially with all the other commands being lowercase?

    • fainpul  1 day ago

      The naming convention is `verb-noun`. It's convenient for discoverability and consistency. The short commands are aliases.

      The last command is properly cased, because I pressed tab (it auto-completes and fixes the case). The other commands I typed without tab completion. You can write however you want, PS is not case sensitive.

  • NSPG911  1 day ago

    i dont think you need to select name and size, you can just remove it and use `select -first 4`, but cool, I never knew about `/=` syntax

    • fainpul  1 day ago

      I was trying to replicate the nushell example, which only has name and size in the output.

BoppreH  2 days ago

For me the best benefit of nushell is not the easier syntax, but the static type checks. It catches most typos before running the script, which is a godsend when the script is slow and/or has destructive operations.

ifh-hn  2 days ago

Was just about to suggest nushell. I love programming in nushell, the out of the box features are excellent.