URLによって表示させるviewを一部変えたいです！

request.path.include?を使い,URLで条件わけしていたのですが#{:id}の部分が機能していません。URLにidが入る時どのような書き方をしたらよろしいでしょうか？どなたかご教授していただけると幸いです！別のviewファイルを作ることも解決策ではあると思いますが、今回はこのメソッドの使い方も含めて理解したいのでこのメソッドの扱い方を教えていただきたいです。（このメソッドというよりは、idの書き方）

http://localhost:3000/mypage/projects/15

request.path.include?("/mypage/projects/#{:id}")

<% if user_signed_in? %>
  <%= javascript_include_tag 'demo_js' %>
    <% if request.path.include?("/mypage/projects/#{:id}")%>
      <nav class="navbar navbar-expand navbar-dark bg-dark">
        <%= link_to "My辞書", :mypage_posts, class:"navbar-brand"%>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="ナビゲーションの切替">
          <span class="navbar-toggler-icon"></span>
        </button>

        <div class="collapse navbar-collapse" id="navbar">
          <ul class="navbar-nav mr-auto">
            <li class="nav-item">
              <%= link_to '辞書を作成する', new_mypage_project_project_post_path(@project), class:"nav-link" %>
            </li>
          </ul>
          <%=form_tag :search_mypage_posts, method: :get, class: "form-inline mt-2 mt-md-0" do%>
            <%= text_field_tag "q", params[:q] , class:"form-control mr-sm-2" %>
            <%= submit_tag "検索" ,class:"btn btn-outline-success my-2 my-sm-0"%>
          <% end %>
        </div>
      </nav>
    <% else %>
      <nav class="navbar navbar-expand navbar-dark bg-dark">
        <%= link_to "My辞書", :mypage_posts, class:"navbar-brand"%>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="ナビゲーションの切替">
          <span class="navbar-toggler-icon"></span>
        </button>

        <div class="collapse navbar-collapse" id="navbar">
          <ul class="navbar-nav mr-auto">
            <li class="nav-item active">
              <%= link_to "Important!!", :important_mypage_posts , class:"nav-link"%>
            </li>
            <li class="nav-item">
              <%= link_to "Most!!", :most_mypage_posts , class:"nav-link"%>
            </li>
            <li class="nav-item">
              <%= link_to '辞書を作成する', new_mypage_post_path, class:"nav-link" %>
            </li>
            <li class="nav-item">
              <%= link_to 'チーム辞書', mypage_projects_path, class:"nav-link" %>
            </li>
          </ul>
          <%=form_tag :search_mypage_posts, method: :get, class: "form-inline mt-2 mt-md-0" do%>
            <%= text_field_tag "q", params[:q] , class:"form-control mr-sm-2" %>
            <%= submit_tag "検索" ,class:"btn btn-outline-success my-2 my-sm-0"%>
          <% end %>
        </div>
      </nav>
    <% end %>
  <% else %>
    <%= javascript_include_tag 'demo_js' %>
    <nav class="navbar navbar-expand navbar-dark bg-dark">
      <%= link_to "My辞書", "/" , class:"navbar-brand"%>
      <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="ナビゲーションの切替">
        <span class="navbar-toggler-icon"></span>
      </button>

      <div class="collapse navbar-collapse" id="navbar">
        <ul class="navbar-nav mr-auto">
          <li class="nav-item active">
            <%= link_to "ユーザー登録", :new_user_registration , class:"nav-link"%>
          </li>
          <li class="nav-item">
            <%= link_to "ログイン", :new_user_session , class:"nav-link"%>
          </li>
        </ul>

      </div>
    </nav>
<% end %>