Why is my javascript code not running? canvas and javascript events

[bobster23]

My javascript code is not running, but the html drawing the canvas is.....Im trying to add an event listener on a canvas html element. Each time i click the element its supposed to give me an alert. Ive tried this on firefox and google chrome. \[code\]<script language = "javascript" type = "text/javascript">alert("yo");canvas.addEventListener('click', function() {}, false);var elem = document.getElementById("checkersq"),elemLeft = elem.offsetLeft,elemTop = elem.offsetTop,context = elem.getContext('2d'),elements = [];elem.addEventListener('click', function(event){ var x = event.pageX - elemLeft, y = event.pageY - elemTop; elements.forEach(function(element){ if (y > element.top && y < element.top + element.height && x > element.left && x < element.left + element.width){ alert('clicked an element'); } } });}, false);elements.push({ colour: '#05EFFF', width: 150, height: 200, top: 20, left: 15});elements.forEach(function(element) { context.fillStyle = element.colour; context.fillRect(element.left, element.top, element.width, element.height);});\[/code\]