title: TypeScript Error: Property '0' is missing in type
body: <p>I have my interface like this </p>
  
  <pre class="lang-js prettyprint-override"><code>export interface Details {
    Name: [{
      First: string;
      Last: string;
    }];
  }   
  </code></pre>
  
  <p>I have an observable config variable:<br/></p>
  
  <p><code>Configuration: KnockoutObservable&lt;Details&gt; = ko.observable&lt;Details&gt;();</code></p>
  
  <p>and I would like to assign it a value in the constructor as follows: </p>
  
  <pre class="lang-js prettyprint-override"><code>config = {
    Name: [{
      First: "ABC",
      Last: "DEF"
    },
    {
      First: "LMN",
      Last: "XYZ"
    }]
  };
  
  this.Configuration(config);
  </code></pre>
  
  <p>and I am getting an error:<br/></p>
  
  <pre><code>Types of property 'Name' is incompatible and property '0' is missing in type.
  Type '{ First:string; Last:string; }[]' is not assignable to 
  type '[{ First: string; Last:string; }]'
  </code></pre>
  
  <p>I don't have control on changing the interface as it is being used elsewhere.<br/> What is the correct way to initialize this config variable ?</p>
  
  <p>Thanks in advance.</p>