As we see in the Rack middleware stack, the last one is`@app=#<ActionDispatch::Routing::RouteSet:0x00007fa1e594cbe8>`

As we see in the Rack middleware stack, the last one is

defserve(req)

params= req.path_parameters# params: { action: 'index', controller: 'home' }

controller= controller(req)# controller: HomeController

res= controller.make_response!(req)# The definition of make_response! is ActionDispatch::Response.create.tap do |res| res.request = request; end

res= controller.make_response!(req)

dispatch(controller, params[:action], req, res)# Let's step into this line.

rescueActionController::RoutingError

It's time to answer the question before:

How canthisinstance variabledefined '@users'in HomeController be accessed in'./app/views/home/index.html.erb'?

How can instance variablelike`@users` definedin`HomeController` be accessed in`./app/views/home/index.html.erb`?

Assume your rails project app class name is`YourProject::Application` (defined in`./config/application.rb`).

First, I will give you a piece of important code.

Then,Let's start rails by`rails server`. The command`rails` locates at`./bin/`.

Then,let's start rails by`rails server`. The command`rails` locates at`./bin/`.

APP_PATH=File.expand_path('../config/application',__dir__)

Now puma has been started successfullyrunning your app (instance of YourProject::Application).

Now puma has been started successfullywith your app (instance of YourProject::Application) running.