rb
With 9 lines of Ruby replace most of the command line tools that you use to process text inside of the terminal.
Here's the code
#!/usr/bin/env ruby
File.join(Dir.home, '.rbrc').tap {, f, load f if File.exists?(f) }
def execute(_, code)
puts _.instance_eval(&code)
rescue Errno::EPIPE
exit
end
single_line = ARGV.delete('-l')
code = eval("Proc.new { #{ARGV.join(' ')} }")
single_line ? STDIN.each {, l, execute(l.chomp, code) } : execute(STDIN.each_line, code)
Clone this repo and copy the rb file to somewhere in your path (or just copy and paste the above).
With this you can use ruby as a command line utility much more ergonomically than invoking it the standard way.
There's only one switch -l which runs your code on each line separately. Otherwise you get an Enumerator that returns the lines of stdin. It's instance_evaled so some methods need self to work, eg. self[-1]
Install
Just paste this line into your terminal to install rb:
sudo curl https://raw.githubusercontent.com/thisredone/rb/master/rb -o /usr/local/bin/rb && sudo chmod +x /usr/local/bin/rb
Examples
Extract docker images from running containers
> docker ps, rb drop 1, rb -l split[1]
# ubuntu
# postgres
Display how much time ago containers have exited
> docker ps -a, rb grep /Exited/, rb -l 'split.last.ljust(20) + " => " + split(/ {2,}/)[-2]'
# angry_hamilton => Exited (0) 18 hours ago
# dreamy_lamport => Exited (0) 3 days ago
# prickly_hypatia => Exited (0) 2 weeks ago
Sort df -h output by Use%
> df -h, rb 'drop(1).sort_by {, l, l.split[-2].to_f }'
# udev 3,9G 0 3,9G 0% /dev
# tmpfs 3,9G 0 3,9G 0% /sys/fs/cgroup
# /dev/sda1 511M 3,4M 508M 1% /boot/efi
# /dev/sda2 237M 85M 140M 38% /boot
# or leave the header if you want
> df -h, rb '[first].concat drop(1).sort_by {, l, l.split[-2].to_f }'
# Filesystem Size Used Avail Use% Mounted on
# udev 3,9G 0 3,9G 0% /dev
# tmpfs 3,9G 0 3,9G 0% /sys/fs/cgroup
# /dev/sda1 511M 3,4M 508M 1% /boot/efi
# /dev/sda2 237M 85M 140M 38% /boot
Count files by their extension
> find . -type f, rb 'group_by(&File.method(:extname)).map {, ext, o, "#{ext.chomp}: #{o.size}" }'
# : 3
# .rb: 19
# .md: 1
This problem http://vegardstikbakke.com/unix/
ls, rb 'group_by {, x, x[/\d+/] }.select {, _, y, y.one? }.keys'
Extending rb
The ~/.rbrc file is loaded if it's available. Anything defined in there will be available inside rb scripts.
# ~/.rbrc
class String
def black; "\033[30m#{self}\033[0m" end
def red; "\033[31m#{self}\033[0m" end
end
> ls, rb first.red