Edit in JSFiddle

// small example by Morten from codesoul.com

function oldStyleWayToYell(count) {
    var res = 'he';
    for (var i = 0; i < count; i++){
        res += "y";
    }  
    return res;
}

var ninja = { 
  yell: function(n){ 
    return n > 0 ? ninja.yell(n-1) + "a" : "hiy"; 
  } 
};

$("#oldyell").text(oldStyleWayToYell(5));
$("#newyell").text(ninja.yell(42));

<p>
  old style way to yell: 
  <span id="oldyell"></span>
</p>
<p>
  functional ninja yell: 
  <span id="newyell"></span>
</p>

p { margin:20px; font-family: 'Segoe UI',Verdana; }
#oldyell {color:red;}
#newyell {color:green;}