    function htmlSelectCode(codeBlock)
      { var e = document.getElementById(codeBlock);
	// Get ID of code block

	// Not IE
	if (window.getSelection)
	{
		var s = window.getSelection();
		// Safari
		if (s.setBaseAndExtent)
		{
			s.setBaseAndExtent(e, 0, e, e.innerText.length - 1);
		}
		// Firefox and Opera
		else
		{
			var r = document.createRange();
			r.selectNodeContents(e);
			s.removeAllRanges();
			s.addRange(r);
		}
	}
	// Some older browsers
	else if (document.getSelection)
	{
		var s = document.getSelection();
		var r = document.createRange();
		r.selectNodeContents(e);
		s.removeAllRanges();
		s.addRange(r);
	}
	// IE
	else if (document.selection)
	{
		var r = document.body.createTextRange();
		r.moveToElementText(e);
		r.select();
	}
      }


    function toggle_visibility(id) {
       var e = document.getElementById(id);
       if(e.style.display == 'none')
          e.style.display = 'block';
       else
          e.style.display = 'none';
    }