title: Enforcing the type of the indexed members of a Typescript object?
body: <p>I would like to store a mapping of string -> string in a Typescript object, and enforce that all of the keys map to strings.  For example:</p>
  
  <pre><code>var stuff = {};
  stuff["a"] = "foo";   // okay
  stuff["b"] = "bar";   // okay
  stuff["c"] = false;   // ERROR!  bool != string
  </code></pre>
  
  <p>Is there a way for me to enforce that the values must be strings (or whatever type..)?</p>