title: Cross-project references between two projects
body: <p>Is it possible to make a reference between two TypeScript projects? Assume we have the following project structure:</p>
  
  <p><img src="https://i.stack.imgur.com/2GwRu.png" alt="Structure"></p>
  
  <p><code>Module1.ts</code> contains:</p>
  
  <pre><code>module TestModule {
      export interface Interface1 {
      }
  }
  </code></pre>
  
  <p><code>Module2.ts</code> contains:</p>
  
  <pre><code>module TestModule {
      export interface Interface2 extends Interface1 {
      }
  }
  </code></pre>
  
  <p><code>Test1</code> is referenced in <code>Test2</code>. I get an error <code>Could not find symbol 'Interface1'</code> in <code>Module2.ts</code>. It works within one project, but I don't know how to make it visible from the other project... Maybe it's not possible for now.</p>
  
  <p><strong>[Edit 1.]</strong><br>
  When I try to use <code>TestModule.Interface1</code> pattern, I get the same error (said in different way). But the IntelliSense sees my <code>Interface1</code>:</p>
  
  <p><img src="https://i.stack.imgur.com/XpDEx.png" alt="IntelliSense"></p>
  
  <p><strong>[Edit 2.]</strong><br>
  I have noticed I can't use files from the other project. Even if I have a correct reference (<code>/// &lt;reference ...</code>) added and linked all the files in my 1st project.</p>