opal-require-dep

If you share code between Rails and Opal, you may run into issues where the explicit requires that Opal (like Ruby without Rails) uses conflict with Rails autoload. There is a solution that has nothing to do with Opal called require_dependency. In Rails, it's ignored and autoloading proceeds as normal. The only problem left is that Opal doesn't know require_dependency is really an alias of require. This fixes that problem.

Add opal-require-dep to your Gemfile:

gem 'opal-require-dep'

If you use Rails or Bundler.require, you don't need to do anything but add to your Gemfile.

If you don't use either of those, then do this on the MRI side:

require 'opal-require-dep'

If you use opal-webpack, then, until this issue is resolved, you'll need to do something like this in your webpack config:

const env = process.env
const path = require('path')

const requireDepLoadPath = path.join(require('child_process').execSync("ruby -e \"puts Gem::Specification.find_by_name('opal-require-dep').gem_dir\"").toString().trim(), 'lib')
env.OPAL_COMPILER_LOAD_PATH = requireDepLoadPath
env.OPAL_COMPILER_REQUIRES = path.join(requireDepLoadPath, 'opal-require-dep')

Then you can use require_dependency in your Opal files that you share with Rails and it will function as an alias of require in Opal

Install required gems at required versions:

$ bundle install

A simple rake task should run the example specs in spec/:

$ bundle exec rake

Authors: Brady Wied

Copyright (c) 2016, BSW Technology Consulting LLC All rights reserved.

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