bug.js

// Is this a JavaScript bug?
// Running the code below alert's "three".

var calls = ["one", "two", "three"]
for(var i in calls) {
 var name = calls[i];
 this[name] = function(){
  alert(name);
 }
}

this.one()

// that's how it actually works:

this['one'] = function() {
  alert(name);
}
this['two'] = function() {
  alert(name);
}
this['three'] = function() {
  alert(name);
}

for (var i in ["one", "two", "three"]) {
  var name = calls[i];
}

// let's check the name
console.log(name); // => "three"

this.one(); // "three", of course