Javascript scoping error function that returns functions

It's kind-of a scope problem. The issue is that each function in the bunch shares the same variable "value". In your case, you forgot to declare "value" with var, so it's a global variable.

Even if you did use var, however, you'd have the same problem.

The trick is to introduce a new layer of scope by wrapping the creation of the function in yet another function.

    bunchOfFunctions[key] = function(valueCopy) {
      return function() {
        alert(valueCopy);
      };
    }(value);

Fiddle of below answer

You will have to replace

  value = obj[key];
  bunchOfFunctions[key] = function(){
      alert(value);
  }

With:

  value = obj[key];
  bunchOfFunctions[key] = (function(value) { return function() {
      alert(value);
  } })(value)

This is because the value variable keeps changing, so once the loop is done running value is 2. What this code does is call a function with value, and that function returns another function. The other function it returns, however, now has the correct value because it is in its own scope.

When the function containing the alert statement runs, it only see the value of the last interaction of the for statement

The solution to avoid this problem is:

var someObj = {"a" : 1, "b" : 2};

function getData(obj){
  var bunchOfFunctions = {};  
  for(var key in obj){
    var value = obj[key];
    bunchOfFunctions[key] = (function(x){
        return function() {
            alert(x);
        }
    })(value)
  }
  return bunchOfFunctions;
}

var functs = getData(someObj);
for(var key in functs){
   functs[key]();
}