minimal pubsub js

minimal_pubsub.js

  var pubsub = function(l, u, r, i) { // cool! 闭包并且初始化vars
    return function(n, f) {
      r = l[n] = l[n] || [], i = -1;
      if (f && f.call) r.push(f);
      else while (r[++i]) r[i].apply(u, arguments);
    }
  }({});

  // subscribe to event
  pubsub("eat_cookie", function() {
    alert("Cookie was eaten");
  });

  // subscribe to another event which expects arguments
  pubsub("bake_cake", function(name, arg1, arg2) {
    alert("Making a cake from " + arg1 + " and " + arg2);
  });
  pubsub("bake_cake", function(name, arg1, arg2) {
    alert("I don't like baking but if I'd bake I'd use " + arg1 + " and " + arg2);
  });

  // trigger events
  pubsub("eat_cookie");
  pubsub("bake_cake", "eggs", "sugar");