Here's a trick I learned today
You've got a Ruby on Rails project with a
Gemfile and a
.ruby-version file at the root of your project, and, as is quite normal, your
Gemfile contains the line
ruby '2.1.0'. Now you want to update Ruby to 2.2.0 so you have to remember to change both the
.ruby-version and the
Gemfile which is a PITA and not especially DRY approach.
Gemfile is just Ruby, so instead of saying
ruby '2.2.0' use
ruby File.read('.ruby-version').match(/(\d+\.\d+\.\d+)/).to_s instead. This will read the Ruby version info directly from your
.ruby-version file and save you some hassle.