Index: node_modules/d3-geo/src/path/area.js
===================================================================
--- node_modules/d3-geo/src/path/area.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
+++ node_modules/d3-geo/src/path/area.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
@@ -0,0 +1,50 @@
+import {Adder} from "d3-array";
+import {abs} from "../math.js";
+import noop from "../noop.js";
+
+var areaSum = new Adder(),
+    areaRingSum = new Adder(),
+    x00,
+    y00,
+    x0,
+    y0;
+
+var areaStream = {
+  point: noop,
+  lineStart: noop,
+  lineEnd: noop,
+  polygonStart: function() {
+    areaStream.lineStart = areaRingStart;
+    areaStream.lineEnd = areaRingEnd;
+  },
+  polygonEnd: function() {
+    areaStream.lineStart = areaStream.lineEnd = areaStream.point = noop;
+    areaSum.add(abs(areaRingSum));
+    areaRingSum = new Adder();
+  },
+  result: function() {
+    var area = areaSum / 2;
+    areaSum = new Adder();
+    return area;
+  }
+};
+
+function areaRingStart() {
+  areaStream.point = areaPointFirst;
+}
+
+function areaPointFirst(x, y) {
+  areaStream.point = areaPoint;
+  x00 = x0 = x, y00 = y0 = y;
+}
+
+function areaPoint(x, y) {
+  areaRingSum.add(y0 * x - x0 * y);
+  x0 = x, y0 = y;
+}
+
+function areaRingEnd() {
+  areaPoint(x00, y00);
+}
+
+export default areaStream;