title: Expected Primary Expression (Solidity)
body: <p>I am creating a simple smart contract, however, I am getting an error on my last function ("ViewNotes") stating that the compiler was "Expected Primary Expression"? Can I not check the value at a mapping (of address => string) against the value <em>0</em> ?</p>
  
  <p>My code: </p>
  
  <pre><code>pragma solidity ^0.4.4;
  
  contract Logistics{
  
  address public owner;
  mapping(address =&gt; string) notes;
  
  modifier onlyOwner() {
      require(msg.sender == owner);
      _;
  }
  
  constructor(address genesis) public {
     owner = genesis;
  }
  
  function sign(string signedNote) public onlyOwner{
          notes[owner] = signedNote; //gaurenteed that msg.sender == owner
  }
  
  function transferOwnership(address nuOwner) onlyOwner {
      owner = nuOwner;
  }
  
  function viewNotes(address participant) public returns(string){ // signed note on success nothing on fail
      if(notes[participant] !== 0){
          return (notes(participant));   
      }
  }
  </code></pre>
  
  <p>}</p>