title: module Myapp.Router.Helpers is not loaded and could not be found
body: <p>A compilation error in an Elixir/Phoenix application:</p>
  
  <pre><code>== Compilation error on file web/views/layout_view.ex ==
  ** (CompileError) web/views/layout_view.ex:2: module Myapp.Router.Helpers is not loaded and could not be found
      expanding macro: Myapp.Web.__using__/1
      web/views/layout_view.ex:2: Myapp.LayoutView (module)
      (elixir) expanding macro: Kernel.use/2
      web/views/layout_view.ex:2: Myapp.LayoutView (module)
      (elixir) lib/kernel/parallel_compiler.ex:117: anonymous fn/4 in Kernel.ParallelCompiler.spawn_compilers/1
  </code></pre>
  
  <p>My web.ex is a standard one, nothing new in it. </p>