[Javascript]Clouse Cove, 2 ,Modifying Bound Values After Closure

function buildCoveTicketMarker(transport){
    var passengerNumber = 0;
    return function(name){
        passengerNumber++;
        alert("Ticket via the "
        +transport+
        "Welcome, "+
        name+
        "#"+passengerNumber+".");
    }
}
var getSubmarineTicket = buildCoveTicketMarker("Submarine");
//passengerNumber number is 1
var getTrianTicket = buildCoveTicketMarker("Train");
//passengerNumber number is 2

The code shows it is still possible the change the variable of the closure in the background.

 

--------------------------Ex------------------------------------

function warningMaker( obstacle ){
  var count = 0;
  return function ( number, location ) {
    count++;
    alert("Beware! There have been " +
          obstacle +
          " sightings in the Cove today!\n" +
          number +
          " " +
          obstacle +
          "(s) spotted at the " +
          location +
          "!\n"+
          "This is Alert #"+
          count+
          " today for "+
          obstacle+
          " danger."
         );
  };
}

//Save location also
function warningMaker( obstacle ){
  var count = 0;
  var locaitons = [];
  return function ( number, location ) {
    locaitons.push(location);
    count++;
    alert("Beware! There have been " +
          obstacle +
          " sightings in the Cove today!\n" +
          number +
          " " +
          obstacle +
          "(s) spotted at the " +
          location +
          "!\n" +
          "This is Alert #" +
          count +
          " today for " +
          obstacle +
          " danger.\n"+
          "Current danger zones are:\n" +
          locaitons.map(function(place){return place+"\n";})
         );
  };
}

//Create a zone object to store location and num
function warningMaker( obstacle ){
  var count = 0;
  var zones = [];
  var zone = {};
  zone.location = "";
  zone.num = 1;
  return function ( number, location ) {
    count++;
    var flag = false;
    for(var j = 0; j < zones.length; j++){
      if(zones[j].location === location){
          zones[j].num++;
        flag = true;
      }
    }
    
    if(!flag){
        zone.location = location;
      zone.num = 1;
      zones.push(zone);
    }
    
    var list = "";
    for(var i = 0; i<zones.length; i++){        
        list = list + "\n" + zones[i].location+" ("+zones[i].num+")";  
    }
    alert("Beware! There have been " +
          obstacle +
          " sightings in the Cove today!\n" +
          number +
          " " +
          obstacle +
          "(s) spotted at the " +
          location +
          "!\n" +
          "This is Alert #" +
          count +
          " today for " +
          obstacle +
          " danger.\n" +
          "Current danger zones are: " +
          list
         );
  };
}