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PORails says class is nil despite console showing database
 

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  1. PORails says class is nil despite console showing database
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    <p>I have a database of objects (tools) in my Ruby on Rails project. When I use "rails dbconsole" and</p> <pre><code>select * from tools; </code></pre> <p>it returns a whole list of tool objects. But when I try to view the following page, it gives me an error. </p> <p>Page:</p> <pre><code> &lt;!DOCTYPE html&gt; &lt;html lang="en"&gt; &lt;%= stylesheet_link_tag "tools", :media =&gt; "all" %&gt; &lt;body&gt; &lt;%= @tools.each do |tool| %&gt; &lt;%= link_to(tool(image_tag.image_url)) %&gt; &lt;% end %&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>Error: </p> <pre><code>undefined method `each' for nil:NilClass </code></pre> <p>When I change the code to add an if statement against nil objects, the page works (without displaying any tools).</p> <pre><code>&lt;% if @tools.nil? %&gt; &lt;% else %&gt; &lt;%= @tools.each do |tool| %&gt; &lt;%= link_to(tool(image_tag.image_url)) %&gt; &lt;% end %&gt; &lt;% end %&gt; </code></pre> <p>So it seems like @tools doesn't have any values in it, but when I look at it in the dbconsole, there are tools there. I can't figure this out, and I've spent the past few days googling for answers, so any and all ideas would be welcome! </p> <p>EDIT: Added tools_controller.rb</p> <pre><code>class ToolsController &lt; ApplicationController before_filter :check_authentication def check_authentication unless session[:user_id] session[:intended_action] = action_name session[:intended_controller] = controller_name redirect_to new_session_url end end def new @tool = Tool.new respond_to do |format| format.html # new.html.erb format.json { render :json =&gt; @tool } end end def show end def index @tools = Tool.all end # GET /tools/1/edit def edit @tool = Tool.find(params[:id]) end # POST /tools # POST /tools.json def create @tool = Tool.new(params[:tool]) respond_to do |format| if @tool.save format.html { redirect_to @tool, :notice =&gt; 'tool was successfully created.' } format.json { render :json =&gt; @tool, :status =&gt; :created, :location =&gt; @tool } else format.html { render :action =&gt; "new" } format.json { render :json =&gt; @tool.errors, :status =&gt; :unprocessable_entity } end end end end </code></pre>
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    1. UScamdroid
    1. UScamdroid
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    1. COPlease include your controller code, which is probably the source of the problem.
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      1. PORails says class is nil despite console showing database
      1. USChris Salzberg
    2. COI've added the controller code. Thanks!
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      1. PORails says class is nil despite console showing database
      1. UScamdroid
    3. CO"But when I try to view the following page" <- which view are you talking about here? If it's for the `index` view then this should work, since you are correctly assigning `@tools = Tool.all`. If it is any other view then it won't work.
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      1. PORails says class is nil despite console showing database
      1. USChris Salzberg
 

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