How to correctly use guard clause in Ruby

问题

What is the correct way to use the guard clause in this sample?

def require_admin
  unless current_user && current_user.role == 'admin'
    flash[:error] = "You are not an admin"
    redirect_to root_path
  end        
end

I don't know where to put flash message when trying to rewrite using these https://github.com/bbatsov/ruby-style-guide#no-nested-conditionals conventions

回答1:

You can use the return statement here. Essentially, there is no need for the method to continue if those conditions are met, so you can bail out early.

def require_admin
  return if current_user && current_user.role == 'admin'

  flash[:error] = "You are not an admin"
  redirect_to root_path
end

来源：https://stackoverflow.com/questions/31943125/how-to-correctly-use-guard-clause-in-ruby