Feature lookup and checking if feature is loaded
$LOADED_FEATURES is useful to know what "files" have been loaded. But it doesn't really tell us what "features" have been loaded. If there where were a way to look-up a load path, without actually loading it then it would be possible to compare that to $LOADED_FEATURES and thus know. e.g.
require 'ostruct' $LOADED_FEATURES #=> [..., "/home/trans/.local/lib/ry/rubies/1.9.3-p125/lib/ruby/1.9.1/ostruct.rb"] path = require_path('ostruct') #=> "/home/trans/.local/lib/ry/rubies/1.9.3-p125/lib/ruby/1.9.1/ostruct.rb" $LOADED_FEATURES.include?(path)
Of course, it would be nice to also have:
required?('ostruct') #=> true
These methods could be class methods of special module, if it's important to keep the Kernel more tidy, e.g.
I am currently working on a project where I need this (and have a couple of other projects that could use it too) and I've had to implement the whole thing from scratch, which isn't simple, nor fast, nor am I 100% confident that it specs exactly to Ruby's own lookup procedure. So it would be much better if Ruby would expose its lookup functionality.