title: How to return mapping list in Solidity? (Ethereum contract)
body: <p>I want to make a simple smart contract that has a list, can set item, and can get the list.</p>
  <p>Code in solidity:</p>
  <pre><code>contract lister {
      mapping(int =&gt; string) list;
      int id = 0;
      
      function getList() returns ( /*HERE*/ ) {
          return list;
      }
  
      function setItemToList(string str) {
          list[id] = str;
          id++;
      }
  }
  </code></pre>
  <p>I want to make getList() return the list, but the return type is not compatible.
  How can I do that?</p>