mb-util

Utility functions for interacting with the operating system, manipulating data, etc. These are things that can't otherwise be categorized, or that are too small to warrant their own project. This is companion code to my educational video series about code and sound.

You might also be interested in mb-sound, mb-geometry, and mb-math.

I recommend using this code only for non-critical tasks.

After following the standalone installation instructions, run bin/console. Pry's ls and show-source -d commands are useful for exploring.

MB::Util.remove_ansi("\e[1mBold\e[0m")
# => 'Bold'

Or, as a console script:

ls --color=force | bin/remove_ansi

txt = MB::Util.highlight({a: 1, b: 2, c: 3}, columns: 10)
# => "{\e[33m:a\e[0m=>\e[1;34m1\e[0m, \e[33m:b\e[0m=>\e[1;34m2\e[0m, \e[33m:c\e[0m=>\e[1;34m3\e[0m}\n"
puts txt
# [prints colorized]
#{:a=>1,
# :b=>2,
# :c=>3}

txt = MB::Util.syntax("def x; {a: 1}; end")
# => "\e[32mdef\e[0m \e[1;34mx\e[0m; {\e[35ma\e[0m: \e[1;34m1\e[0m}; \e[32mend\e[0m"
puts txt
# [prints colorized]
# def x; {a: 1}; end

data = {
  a: [1, 2, 3],
  b: [4, 5, 6],
}
MB::U.table(data)

The data is printed to the terminal (but with colors not visible here):

 a | b
---+---
 1 | 4
 2 | 5
 3 | 6

You can use Unicode box-drawing characters instead if you like (see the method documentation for all the options):

MB::U.table(data, unicode: true)

 a │ b
───┼───
 1 │ 4
 2 │ 5
 3 │ 6

Sometimes you want to know what an application is doing without interrupting it. This might even be a production web app running on a remote server where options for debugging are limited. You can use sigquit_backtrace to install a signal handler that will print a trace for all threads if you send SIGQUIT to your application.

In your application:

# In your app's startup
MB::U.sigquit_backtrace

# Note: the output is a little more useful if you give your threads names
Thread.current.name = 'Main thread'

To generate a trace:

# From a terminal
kill -QUIT [your_app_pid]

# Or, press Ctrl-\ in the terminal where your app is running

And see the output (note that the output has colors not visible here):

Thread #<Thread:0x0000559e391bed88 run> (current thread)
========================================================
~/devel/mb-util/lib/mb/util/debug_methods.rb:23:in `backtrace'
~/devel/mb-util/lib/mb/util/debug_methods.rb:23:in `block (2 levels) in sigquit_backtrace'
~/devel/mb-util/lib/mb/util/debug_methods.rb:21:in `each'
~/devel/mb-util/lib/mb/util/debug_methods.rb:21:in `block in sigquit_backtrace'
~/.rvm/gems/ruby-2.7.8@mb-util/gems/pry-0.14.1/lib/pry/repl.rb:198:in `readline'
~/.rvm/gems/ruby-2.7.8@mb-util/gems/pry-0.14.1/lib/pry/repl.rb:198:in `block in input_readline'
.
.
.

This project can be experimented with by cloning the Git repo, or you can use it as a Gem (with Git source) in your own projects.

First, install a Ruby version manager like RVM. Using the system's Ruby is not recommended -- that is only for applications that come with the system. You should follow the instructions from https://rvm.io, but here are the basics:

gpg2 --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
\curl -sSL https://get.rvm.io | bash -s stable

Next, install Ruby. RVM binary rubies are still broken on Ubuntu 20.04.x, so use the --disable-binary option if you are running Ubuntu 20.04.x.

rvm install --disable-binary 2.7.3

You can tell RVM to isolate all your projects and switch Ruby versions automatically by creating .ruby-version and .ruby-gemset files (already present in this project):

cd mb-util
cat .ruby-gemset
cat .ruby-version

Now install dependencies:

bundle install

To use mb-util in your own Ruby projects, add this Git repo to your Gemfile:

# your-project/Gemfile
gem 'mb-util', git: 'https://github.com/mike-bourgeous/mb-util.git

The utility functions will make use of the coderay, pry, and word_wrap Gems if they are available in your project, but these are optional:

gem 'pry'
gem 'coderay'
gem 'word_wrap'

Run rspec.

Pull requests welcome, though development is focused specifically on the needs of my video series.

This project is released under a 2-clause BSD license. See the LICENSE file.

• Pry (optional)
• CodeRay (optional)
• WordWrap (optional)

• Terminal color sequences