From ab1060e864f73a50a782f61092298137062e7f89 Mon Sep 17 00:00:00 2001
From: Mike Bostock <mbostock@gmail.com>
Date: Mon, 29 Nov 2021 13:01:04 -0800
Subject: [PATCH] insertBefore, insertAfter

---
 src/selection/index.js  |  4 +++-
 src/selection/insert.js | 16 ++++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/selection/index.js b/src/selection/index.js
index a593a21..99453e8 100644
--- a/src/selection/index.js
+++ b/src/selection/index.js
@@ -25,7 +25,7 @@ import selection_html from "./html.js";
 import selection_raise from "./raise.js";
 import selection_lower from "./lower.js";
 import selection_append from "./append.js";
-import selection_insert from "./insert.js";
+import selection_insert, {insertAfter, insertBefore} from "./insert.js";
 import selection_remove from "./remove.js";
 import selection_clone from "./clone.js";
 import selection_datum from "./datum.js";
@@ -79,6 +79,8 @@ Selection.prototype = selection.prototype = {
   lower: selection_lower,
   append: selection_append,
   insert: selection_insert,
+  insertAfter,
+  insertBefore,
   remove: selection_remove,
   clone: selection_clone,
   datum: selection_datum,
diff --git a/src/selection/insert.js b/src/selection/insert.js
index 1733de5..bccdaf3 100644
--- a/src/selection/insert.js
+++ b/src/selection/insert.js
@@ -5,6 +5,14 @@ function constantNull() {
   return null;
 }
 
+function selectThis() {
+  return this;
+}
+
+function selectNextSibling() {
+  return this.nextSibling;
+}
+
 export default function(name, before) {
   var create = typeof name === "function" ? name : creator(name),
       select = before == null ? constantNull : typeof before === "function" ? before : selector(before);
@@ -12,3 +20,11 @@ export default function(name, before) {
     return this.insertBefore(create.apply(this, arguments), select.apply(this, arguments) || null);
   });
 }
+
+export function insertBefore(name) {
+  return this.insert(name, selectThis);
+}
+
+export function insertAfter(name) {
+  return this.insert(name, selectNextSibling);
+}