title: How can I create a new instance of ImmutableDictionary?
body: <p>I would like to write something like this:</p>
  
  <pre><code>var d = new ImmutableDictionary&lt;string, int&gt; { { "a", 1 }, { "b", 2 } };
  </code></pre>
  
  <p>(using <code>ImmutableDictionary</code> from <a href="http://www.nuget.org/packages/Microsoft.Bcl.Immutable/" rel="noreferrer">System.Collections.Immutable</a>). It seems like a straightforward usage as I am declaring all the values upfront -- no mutation there. But this gives me error:</p>
  
  <blockquote>
    <p>The type '<code>System.Collections.Immutable.ImmutableDictionary&lt;TKey,TValue&gt;</code>' has no constructors defined</p>
  </blockquote>
  
  <p>How I am supposed to create a new immutable dictionary with static content?</p>