Index: node_modules/d3-selection/src/selection/property.js
===================================================================
--- node_modules/d3-selection/src/selection/property.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
+++ node_modules/d3-selection/src/selection/property.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
@@ -0,0 +1,28 @@
+function propertyRemove(name) {
+  return function() {
+    delete this[name];
+  };
+}
+
+function propertyConstant(name, value) {
+  return function() {
+    this[name] = value;
+  };
+}
+
+function propertyFunction(name, value) {
+  return function() {
+    var v = value.apply(this, arguments);
+    if (v == null) delete this[name];
+    else this[name] = v;
+  };
+}
+
+export default function(name, value) {
+  return arguments.length > 1
+      ? this.each((value == null
+          ? propertyRemove : typeof value === "function"
+          ? propertyFunction
+          : propertyConstant)(name, value))
+      : this.node()[name];
+}