`String#underscore` Ruby Extension

fast_underscore is a simple C extension which provides a fast implementation of Active Support's String#underscore method.

Do I need this?

Maybe! Run a stack profiler like ruby-prof. If String#underscore or ActiveSupport::Inflector#underscore is coming up near the top of the list, this gem might be for you! If not, you probably don't need it. Either way, your milage may vary depending on the type of strings on which you're calling underscore.

Usage with Rails

ActiveSupport::Inflector#underscore is actually used significantly throughout the Rails boot process, so it's best to hook into that process early to get the best results. Place the following lines above the require 'rails' line in your application.rb file:

require 'active_support'
require 'fast_underscore'

This will allow Rails to use the faster underscore method while it is booting, which is used for autoloading dependencies, as well as determining table names.

Is it fast?

At last check, these were the benchmarks (obtained by running bin/benchmark):

Warming up --------------------------------------
       ActiveSupport     2.000  i/100ms
      FastUnderscore    64.000  i/100ms
Calculating -------------------------------------
       ActiveSupport     28.839  (± 6.9%) i/s -    144.000  in   5.019140s
      FastUnderscore    650.151  (± 7.7%) i/s -      3.264k in   5.056094s

Comparison:
      FastUnderscore:      650.2 i/s
       ActiveSupport:       28.8 i/s - 22.54x  slower

Installation

Add this line to your application's Gemfile:

gem 'fast_underscore'

And then execute:

$ bundle

Or install it yourself as:

$ gem install fast_underscore

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/kddeisz/fast_underscore.

License

The gem is available as open source under the terms of the MIT License.

String#underscore Ruby Extension