function run_my_code($) {
    // jquery-dependent code here
    $("#foo").data('bar', true);
}
var t = null;
function jquery_ready() {
    if (window.jQuery && window.jQuery.ui) {
        run_my_code(window.jQuery);
    } else {
        t = window.setTimeout(jquery_ready, 100);
    }
}
t = window.setTimeout(jquery_ready, 100);

(function() {
  var runMyCode = function($) {
    // jquery-dependent code here
    $("#foo").data('bar', true);
  };

  var timer = function() {
    if (window.jQuery && window.jQuery.ui) {
      runMyCode(window.jQuery);
    } else {
      window.setTimeout(timer, 100);
    }
  };
  timer();
})();

var Namespace = Namespace || { };
Namespace.Deferred = function () {
  var functions = [];
  var timer = function() {
    if (window.jQuery && window.jQuery.ui) {
        while (functions.length) {
            functions.shift()(window.jQuery);
        }
    } else {
        window.setTimeout(timer, 250);
    }
  };
  timer();
  return {
    execute: function(onJQueryReady) {
        if (window.jQuery && window.jQuery.ui) {
            onJQueryReady(window.jQuery);
        } else {
            functions.push(onJQueryReady);
        }
    }
  };
}();

Namespace.Deferred.execute(runMyCode);

<script>
if ( ! window.deferAfterjQueryLoaded ) {
    window.deferAfterjQueryLoaded = [];
    Object.defineProperty(window, "$", {
        set: function(value) {
            window.setTimeout(function() {
                $.each(window.deferAfterjQueryLoaded, function(index, fn) {
                    fn();
                });
            }, 0);
            Object.defineProperty(window, "$", { value: value });
        },

        configurable: true
    });
}

window.deferAfterjQueryLoaded.push(function() {
    //... some code that needs to be run
});
</script>

<script>
    window.deferAfterjQueryLoaded = [];
    window.deferAfterjQueryLoaded.push(function() {
        //... some code that needs to be run
    });

    // ... further down in the page

    window.deferAfterjQueryLoaded.push(function() {
        //... some other code to run
    });
</script>

<script src="jquery.js" />
<script>
    $.each(window.deferAfterjQueryLoaded, function(index, fn) {
        fn();
    });
</script>

window.deferAfterjQueryLoaded.push(function() {
    $(function() {
        console.log('jquery loaded and the DOM is ready');
    });
    console.log('jquery loaded');
});

function RunAfterjQ(){
// Codes that uses jQuery
}

<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
<script type="text/javascript">
    RunAfterjQ();
</script>

var afterJQ = [];

<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
<script type="text/javascript">
    for(var i=0; i < afterJQ; i++) afterJQ[i]();
</script>

after.JQ.push( function() {
    // this code will execute after jQuery is loaded.
 });

head.ready(function(){
  $...
});

head.js('/jquery.min.js');

document.addEventListener("DOMContentLoaded", function(event) {
    //you can use jQuery there
});

<!-- jQuery defer code body: deferring jQuery calls until jQuery is loaded -->
<script>
  window.jQueryQ = window.jQueryQ || [];
  window.$ = window.jQuery = function(){
    window.jQueryQ.push(arguments);
  }
</script>
<!-- end: jQuery defer code body -->

<!-- jQuery deferring code footer: add this to the end of body and after the jQuery code -->
<script>
  jQuery(function(){
    jQuery.each(window.jQueryQ||[],function(i,a){
      // to understand why setTimeout 0 is useful, see: https://www.youtube.com/watch?v=8aGhZQkoFbQ, tldr: having a lot of calls wont freeze the website
      setTimeout(function(){
        jQuery.apply(this,a);
      },0);
    });
  });
</script>
<!-- end: jQuery deferring code footer -->