closure_alternatives.js

////////////////////////////
// using inline closure
////////////////////////////
(function() {  
  arr = []
  
  for (i = 0; i < 10; i++)
    arr[i] = (function(i) {
      return function() { console.log("I am #" + i) }
    })(i)
  
  for (j = 0; j < 10; j++)
    arr[j]()
})()

/////////////////////////////////
// using closure in a function
/////////////////////////////////
(function() {  
  arr = []
  
  function closure(i, fn) {
    return function() { return fn(i) }
  }
    
  for (i = 0; i < 10; i++)
    arr[i] = closure(i, function(i) { console.log("I am #" + i) })
    
  for (j = 0; j < 10; j++)
    arr[j]()
})()

//////////////////////////////
// using Function constructor
//////////////////////////////
(function() {
  arr = []
  
  for (i = 0; i < 10; i++)
    arr[i] = Function("console.log('I am #" + i + "')")
    
  for (j = 0; j < 10; j++)
    arr[j]()
})()

/////////////////////////////
// using bind 
/////////////////////////////
(function() {
  arr = []
  
  for (i = 0; i < 10; i++)
    arr[i] = function(i) { console.log("I am #" + i) }.bind(null, i)
    
  for (j = 0; j < 10; j++)
    arr[j]()
})()

//////////////////////////////
// using let (requires ES6)
//////////////////////////////
// In Chrome (v46) ! I have to use strict mode to use "let" 
//  ~ which also does not allow globals
//  ~ so we must add var in front of variable names
(function() {
  'use strict'
  var arr = []
  
  for (let i = 0; i < 10; i++) 
    arr[i] = function() { console.log("I am #" + i) }
    
  for (var j = 0; j < 10; j++) 
    arr[j]()
})()

////////////////////////
// using currying
////////////////////////
(function() {  
  arr = []
  function curry(i) { 
    return function(fn) { 
      return function() { 
        return fn(i) 
      } 
    } 
  }
  
  for (i = 0; i < 10; i++) 
    arr[i] = curry(i)(function(i) { console.log("I am #" + i) })
    
  for (j = 0; j < 10; j++) 
    arr[j]()
})()

/////////////////////////
// using Array functions
/////////////////////////
(function() {  
  arr = Array(10)
  arr.fill(null)
     .forEach(function(_, i) { 
       arr[i] = function() { console.log("I am #" + i) }
     })
     
  for (j = 0; j < 10; j++) 
    arr[j]()
})()

/////////////////////////////
// using time indexing array
/////////////////////////////
(function() {  
  arr = []
  t = [] // time index -- stores a value at each loop interation
  
  for (i = 0; i < 10; i++) {
    t[i] = i // you could record any value for this time point
    arr[i] = function(i) { console.log("I am #" + i) }
  }
  
  for (j = 0; j < 10; j++)
    arr[j](t[j]) // Note: this function invocation is different than other alternatives
})()

Added two more alternatives: http://jsperf.com/closure-alternativess/4