title: How to create a Roslyn ITypeSymbol for an arbitrary type?
body: <p>I can use a <strong>SyntaxGenerator</strong> to generate a parameter of type <strong>Int32</strong> like so...</p>
  
  <pre><code>var generator = SyntaxGenerator.GetGenerator(document);
  var paramType = generator.TypeExpression(SpecialType.System_Int32);
  var param = generator.ParameterDeclaration("MyParam", paramType);
  </code></pre>
  
  <p>What equivalent code should I use to create a parameter of type <strong>Dataset</strong>?</p>
  
  <p>I presume I need to create an <strong>ITypeSymbol</strong> to pass to the <strong>generator.TypeExpression</strong>, but how to do this?</p>