From ac58c65537d6d31a80e2253ae038c36a215f09fc Mon Sep 17 00:00:00 2001
From: Abel Braaksma <abel.online@xs4all.nl>
Date: Tue, 19 Dec 2023 03:20:42 +0100
Subject: [PATCH] Fix `truncate`, do not `MoveNext` before we know we have
 enough elements

---
 src/FSharp.Control.TaskSeq/TaskSeqInternal.fs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/FSharp.Control.TaskSeq/TaskSeqInternal.fs b/src/FSharp.Control.TaskSeq/TaskSeqInternal.fs
index 6704d868..9915f358 100644
--- a/src/FSharp.Control.TaskSeq/TaskSeqInternal.fs
+++ b/src/FSharp.Control.TaskSeq/TaskSeqInternal.fs
@@ -721,8 +721,12 @@ module internal TaskSeqInternal =
                     while cont do
                         yield e.Current
                         pos <- pos + 1
-                        let! moveNext = e.MoveNextAsync()
-                        cont <- moveNext && pos < count
+
+                        if pos < count then
+                            let! moveNext = e.MoveNextAsync()
+                            cont <- moveNext
+                        else
+                            cont <- false
 
                 }