The syncLoop() function creates a recursive, synchronous loop executed for each element of a given array and accepts callbacks. Example appliance: wait for user input before proceeding to the next element, without the need to execute the loop asynchronously (useful for dynamic code / metaprogramming) Notice that tail recursion isn't optimized in…

syncLoop.js

/*  
 *  The syncLoop() function creates a synchronous loop 
 *  that executes recursively for each element of a given array 
 *  and accepts callbacks.
 *  
 *  I needed to wait for user input inside the loop and
 *  could not use process the elements asynchronously
 *  thus, here is the syncLoop()
 */
 
// Define the array to be iterated
var arr = ["my", "array"];

// Define the function to be executed on each element. The callback is used to iterate through the array
function insideTheLoop(arg1, callback) {
  // your code
  callback();
}
// Define the argument for insideLoop()
var arg1;

// Define callback to be executed after the syncLoop() ends
function loopCallback() {
  // your code
}

// the syncLoop
function syncLoop(arr, i, loopCallback) {
  if (i < arr.length) {
    insideTheLoop(arg1, function() {
      i++;
      syncLoop(arr, i, loopCallback);
    });
  }
  else {
    loopCallback();
  }
}

// Set the helper variable to 0
var i = 0;

// Call the function
syncLoop(arr, i, loopCallback);