title: bcrypt always returns false
body: <p>I am trying to store the hash password and checking the it is valid or not.</p>
  
  <pre><code>var bcrypt = require('bcrypt');
  let data = "";
  
  bcrypt.genSalt(10, function(err, salt) {
      bcrypt.hash("my password", salt, function(err, hash) {
          // Store hash in your password DB.
          console.log(hash);
          data = hash;
      });
  });
  
  bcrypt.compare("my password", data, function(err, res) {
      // res === true
      console.log(res)
  });
  </code></pre>
  
  <p>return value always false.?</p>
  
  <p>but if I move the compare inside genSalt function its returning true.</p>
  
  <p>Thanks</p>