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Ruby

Posted by Shaun Jackson
Shaun Jackson
1,270 Points

Undefined method for nil:NilClass

I thought everything was going so well until...

Yep see, another bug already?

undefined method `full_name' for nil:NilClass

17:     <li class="active"><%= link_to "Log Out", destroy_user_session_path %></li>
18:     </ul>
19:     <ul class="nav pull-right">
20:     <li><%= link_to current_user.full_name, "#" %></li>
21:     </ul>
22:     </div>
23:   </div>

Here is the full code from application layout:

<!DOCTYPE html>
<html>
<head>
  <title>Treebook</title>
  <%= stylesheet_link_tag    "application", :media => "all" %>
  <%= javascript_include_tag "application" %>
  <%= csrf_meta_tags %>
</head>
<body>
    <div class="navbar">
    <div class="navbar-inner">
    <a class="brand" href="#">Faceown</a>
    <ul class="nav">
    <li class="active"><%= link_to "New Ownage", new_status_path %></li>
    <li class="active"><%= link_to "All Statuses", statuses_path %></li>
    <li class="active"><%= link_to "Sign Up", new_user_registration_path %></li>
    <li class="active"><%= link_to "Log Out", destroy_user_session_path %></li>
    </ul>
    <ul class="nav pull-right">
    <li><%= link_to current_user.full_name, "#" %></li>
    </ul>
    </div>
  </div>
<div class="container">
<p class="notice"><%= notice %></p>
<p class="alert"><%= alert %></p>  
<%= yield %>
</div>

</body>
</html>

I've checked the code and below is the code shown for full_name def.

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  # Setup accessible (or protected) attributes for your model
  attr_accessible :email, :password, :password_confirmation, 
  :remember_me, :first_name, :last_name, :profile_name
  # attr_accessible :title, :body

has_many :statuses

def full_name
    first_name + " " + last_name
end

end

2 Answers

Shaun Jackson
Shaun Jackson
1,270 Points

Got it :)

   <% if user_signed_in? %>
    <ul class="nav pull-right">
    <li class="active"><%= link_to "Log Out", destroy_user_session_path, method: :delete %></li>
    <li><%= link_to current_user.full_name, edit_user_registration_path %></li>
    <% end %>
    </ul>
Alan Johnson
Alan Johnson
7,625 Points

Awesome! Glad you figured it all out. Sorry about the syntax error there - I was tossing up possible solutions without having the project in front of me.

Alan Johnson
Alan Johnson
7,625 Points
Alan Johnson
Alan Johnson
7,625 Points

So when you get undefined method X for nil:NilClass usually the issue is that you're calling a method on a nil object, so it doesn't exist. In this case you're calling:

current_user.full_name

but current_user is nil. There are a couple of ways you'd usually work around that. The first is to make sure current_user is only called when someone is logged in (are you logged in?) and the other is to always check that current_user is present before calling it:

<li><%= link_to(current_user.full_name, "#") if current_user.present? %></li>
Shaun Jackson
Shaun Jackson
1,270 Points

Hi Alan,

Yes I was logged in and tried your method but got the following error:

SyntaxError in Statuses#index

Showing C:/Sites/treebook/app/views/layouts/application.html.erb where line #20 raised: 

17:     <li class="active"><%= link_to "Log Out", destroy_user_session_path %></li>
18:     </ul>
19:     <ul class="nav pull-right">
20:     <li><%= link_to current_user.full_name, "#") if current_user.present? %></li>
21:     </ul>
22:     </div>
23:   </div>