function d3_svg_area(projection) {

  var x0 = d3_svg_lineX,

      x1 = d3_svg_lineX,

      y0 = 0,

      y1 = d3_svg_lineY,

      interpolate,

      i0,

      i1,

      tension = .7;

  function area(d) {

    if (d.length < 1) return null;

    var points0 = d3_svg_linePoints(this, d, x0, y0),

        points1 = d3_svg_linePoints(this, d, x0 === x1 ? d3_svg_areaX(points0) : x1, y0 === y1 ? d3_svg_areaY(points0) : y1);

    return "M" + i0(projection(points1), tension)

         + "L" + i1(projection(points0.reverse()), tension)

         + "Z";

  }

  area.x = function(x) {

    if (!arguments.length) return x1;

    x0 = x1 = x;

    return area;

  };

  area.x0 = function(x) {

    if (!arguments.length) return x0;

    x0 = x;

    return area;

  };

  area.x1 = function(x) {

    if (!arguments.length) return x1;

    x1 = x;

    return area;

  };

  area.y = function(y) {

    if (!arguments.length) return y1;

    y0 = y1 = y;

    return area;

  };

  area.y0 = function(y) {

    if (!arguments.length) return y0;

    y0 = y;

    return area;

  };

  area.y1 = function(y) {

    if (!arguments.length) return y1;

    y1 = y;

    return area;

  };

  area.interpolate = function(x) {

    if (!arguments.length) return interpolate;

    i0 = d3_svg_lineInterpolators[interpolate = x];

    i1 = i0.reverse || i0;

    return area;

  };

  area.tension = function(x) {

    if (!arguments.length) return tension;

    tension = x;

    return area;

  };

  return area.interpolate("linear");

}

d3_svg_lineStepBefore.reverse = d3_svg_lineStepAfter;

d3_svg_lineStepAfter.reverse = d3_svg_lineStepBefore;

d3.svg.area = function() {

  return d3_svg_area(Object);

};

function d3_svg_areaX(points) {

  return function(d, i) {

    return points[i][0];

  };

}

function d3_svg_areaY(points) {

  return function(d, i) {

    return points[i][1];

  };

}