anchor.diff:  ```javascript
   var asciidoctor = Asciidoctor(); // <1>
   var content = "http://asciidoctor.org[*Asciidoctor*] " +
  -    "running on http://opalrb.org[_Opal_] " +
  +    "running on https://opalrb.com[_Opal_] " +
       "brings AsciiDoc to the browser!";
   var html = asciidoctor.convert(content); // <2>
   console.log(html); // <3>
  
positive.code: [.output]
  
      <div class="paragraph">
      <p><a href="http://asciidoctor.org"><strong>Asciidoctor</strong></a> running on <a href="http://opalrb.org"><em>Opal</em></a> brings AsciiDoc to Node.js!</p>
      </div>
  
  == Advanced topics
  
negative.code: ifdef::env-github[]
  image:https://img.shields.io/travis/asciidoctor/asciidoctor.js/master.svg[Travis build status, link=https://travis-ci.org/asciidoctor/asciidoctor.js]
  image:https://ci.appveyor.com/api/projects/status/i69sqvvyr95sf6i7/branch/master?svg=true[Appveyor build status, link=https://ci.appveyor.com/project/asciidoctor/asciidoctor-js]
  image:https://img.shields.io/npm/v/asciidoctor.js.svg[npm version, link=https://www.npmjs.org/package/asciidoctor.js]
  image:https://img.shields.io/cdnjs/v/asciidoctor.js.svg[cdnjs, link=https://cdnjs.com/libraries/asciidoctor.js]
  image:https://img.shields.io/badge/jsdoc-master-blue.svg[JSDoc, link=http://asciidoctor.github.io/asciidoctor.js/master]
  image:https://inch-ci.org/github/asciidoctor/asciidoctor.js.svg?branch=master[InchCI, link=https://inch-ci.org/github/asciidoctor/asciidoctor.js]
  