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 1var getTrianTicket = buildCoveTicketMarker("Train");//passengerNumber number is 2

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

 

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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 alsofunction 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 numfunction 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