map reduce, javascript

mapReduce

 var users = [
            {name:'johndoe', password: 'secret', displayName: 'John Doe'},
            {name:'elladoe', password: 'secret', displayName: 'Ella Doe'},
            {name:'minidoe', password: 'secret', displayName: 'Mini Doe'}
  ];
  
  var username = 'johndoe';
  
  // return current user or null if not found
  var user = users.map(function(user){
          return user.name === username ? user : null;
      }).reduce(function(prev, curr){
          return curr || prev;
      });