function (when, len, attrs) {
      var x = time_x(when);
      var end_y = ui.y + len;
      var e = paper.path(
        "M" + x + "," + ui.y + " " +
        "L" + x + "," + end_y
      ).attr(attrs || {});
      return e;    
    }
function (when, len, attrs) {
      var x = time_x(when);
      var end_y = ui.y + len;
      var e = paper.path(
        "M" + x + "," + ui.y + " " +
        "L" + x + "," + end_y
      ).attr(attrs || {});
      return e;    
    }
function ( when , len , attrs ) { var x = time_x ( when ) ; var end_y = ui . y + len ; var e = paper . path ( "M" + x + "," + ui . y + " " + "L" + x + "," + end_y ) . attr ( attrs || { } ) ; return e ; }
draw a line at when from y as far as len pixels with attrs.
draw a line at when from y as far as len pixels with attrs .