From 5979e3c52ee18ed881878174fdf16b6e3e606200 Mon Sep 17 00:00:00 2001
From: joMarsch <106771284+joMarsch@users.noreply.github.com>
Date: Wed, 18 Sep 2024 08:21:28 +0200
Subject: [PATCH] Update about.md (#1279)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The accumulator needs to be returned by the functions otherwise the won’t work correctly.
---
 concepts/recursion/about.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/concepts/recursion/about.md b/concepts/recursion/about.md
index 3f4ed177e..991e30127 100644
--- a/concepts/recursion/about.md
+++ b/concepts/recursion/about.md
@@ -39,7 +39,7 @@ Here is a tail-recursive version of the list length function:
 ```fsharp
 let rec lengthRecursive acc list =
     match list with
-    | [] -> 0
+    | [] -> acc
     | x::xs -> lengthRecursive (acc + 1) xs
 
 let length list = lengthRecursive 0 list
@@ -51,7 +51,7 @@ It is quite common to define the recursive helper as a nested function, which hi
 let length list =
     let rec lengthRecursive acc remainder =
         match remainder with
-        | [] -> 0
+        | [] -> acc
         | x::xs -> lengthRecursive (acc + 1) xs
 
     lengthRecursive 0 list