With 10 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
def execute(_, code)
puts _.instance_eval(&code)
rescue Errno::EPIPE
exit
end
single_line = ARGV[0] == '-l'
expr = ARGV.drop(single_line ? 1 : 0).join(' ')
code = eval("Proc.new { #{expr} }")
single_line ? STDIN.each { |l| execute(l.chomp, code) } : execute(STDIN.readlines, 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 the whole stdin as an Array of lines. It's instance_evaled so some methods need self to work, eg. self[-1]
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
> docker ps | rb drop 1 | rb -l split[1]
# ubuntu
# postgres> 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> 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