title: Inject JS global var in Jade template
body: <p>I have a form that is created in Jade ans then compiled. I need to pass the Label name with Javascript.
  So the javascript var will look like this :</p>
  
  <pre><code>var trans = {"formFirstName": "First Name"}
  </code></pre>
  
  <p>in the form.jade currently its </p>
  
  <pre><code>.field.first_name
    label First Name
    .input-wrapper
      input(type="text")
  </code></pre>
  
  <p>But I want First Name to be the variable. I am very new in jade and node. I have no idea how to do that. </p>