From d3e6cf9e0fc0cc9bf4b631988525e271d4504d37 Mon Sep 17 00:00:00 2001
From: make-github-pseudonymous-again
 <5165674+make-github-pseudonymous-again@users.noreply.github.com>
Date: Sun, 13 Nov 2022 18:53:26 +0100
Subject: [PATCH] :recycle: refactor: Extract _extend from from.

---
 src/_extend.js | 21 +++++++++++++++++++++
 src/from.js    |  9 ++-------
 src/index.js   |  1 +
 3 files changed, 24 insertions(+), 7 deletions(-)
 create mode 100644 src/_extend.js

diff --git a/src/_extend.js b/src/_extend.js
new file mode 100644
index 0000000..bcfbae8
--- /dev/null
+++ b/src/_extend.js
@@ -0,0 +1,21 @@
+import assert from 'assert';
+import Node from './Node.js';
+import _push from './_push.js';
+
+/**
+ * Extend a list with an iterable.
+ *
+ * @param {Node} z The last node of the list to extend.
+ * @param {Iterable} iterable The input iterable.
+ * @return {Node} Last node of the extended list.
+ */
+export default function _extend(z, iterable) {
+	assert(z instanceof Node);
+	let y = z;
+
+	for (const value of iterable) {
+		y = _push(y, value);
+	}
+
+	return y;
+}
diff --git a/src/from.js b/src/from.js
index 19d903d..f769fff 100644
--- a/src/from.js
+++ b/src/from.js
@@ -1,5 +1,5 @@
 import Node from './Node.js';
-import _push from './_push.js';
+import _extend from './_extend.js';
 
 /**
  * Creates a list from an input iterable.
@@ -14,11 +14,6 @@ export default function from(iterable) {
 	if (event.done) return null;
 
 	const first = new Node(event.value, null, null);
-	let last = first;
-
-	for (const value of it) {
-		last = _push(last, value);
-	}
-
+	_extend(first, it);
 	return first;
 }
diff --git a/src/index.js b/src/index.js
index a767383..043019f 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,5 +1,6 @@
 export {default as Node} from './Node.js';
 export {default as _concat} from './_concat.js';
+export {default as _extend} from './_extend.js';
 export {default as _iter} from './_iter.js';
 export {default as _iter_fast} from './_iter_fast.js';
 export {default as _last} from './_last.js';