How to hint an asynchronous operation with a JavaScript promise? -


For learning purposes, I want to show how to help resolve the dependency at the time of database operation in Javascript can do.

So, I want to show this: 

  db.find (14);   
 Actually consumes the time behind the curtain.  
 How can I explain the dependence and a possible solution at this time which promises?  
 Do I still have this:  
  // Take the data store operation time function _findByUsername (username) {var user = _.findWhere (user, {username} : Username}); If (! User) {Promise.reject (new error ("user not found.")); } Return Plaintiff. User (user); }   
 
 
 One option may be to use the function of the bluebird and a comment Can be added as follows:  
  findByUsername (username) {/ * simulates the behavior of a database operation / / Promise.delay return (10). Then the setter (_. FindWhere (user, {username: user name})}

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