Posted almost 3 years ago. Visible to the public. Repeats.

Ruby: __FILE__, __dir__ and symlinks

Ruby's __FILE__ keyword returns the path to the current file. On popular for this are Ruby binaries:

#!/usr/bin/env ruby $LOAD_PATH << File.expand_path('../../lib', __FILE__) require 'my_cli'!

However, if you create a symlink to this file, this will no longer work. __FILE__ will resolve to the path of the symlink, not to its target.

One solution is to use File.realpath(__FILE__).

In Ruby 2+ you can also use this:

$LOAD_PATH << File.expand_path('../lib', __dir__)

__dir__ is simply a shortcut for File.dirname(File.realpath(__FILE__)).

Growing Rails Applications in Practice
Check out our new e-book:
Learn to structure large Ruby on Rails codebases with the tools you already know and love.

Owner of this card:

Tobias Kraze
Last edit:
11 months ago
by Tobias Kraze
About this deck:
We are makandra and do test-driven, agile Ruby on Rails software development.
License for source code
Posted by Tobias Kraze to makandra dev
This website uses cookies to improve usability and analyze traffic.
Accept or learn more