kodfejtok_sample.js

(function(app) {
  var blockNodes, complexComputation,
      findNodes, hiddenNodes, hide;

  complexComputation = function () {
    /* do some complex stuff and return a node */
  };

  findNodes = function(callback) {
    var nodes = [], node;

    node = complexComputation();
    // call if callback is callable
    if (typeof callback === "function") callback(node);
    nodes.push(node);
    return nodes;
  };

  // a callback function
  hide = function(node) {
    node.style.display = "none";
  };

  // find the nodes and hide them as you go
  hiddenNodes = findNodes(hide);

  blockNodes  = findNodes(function(node) {
    node.style.display = 'block';
  });
})(this);