From 5fc7577b5a3bc2c445522dfd5b287e1c6eddc3e9 Mon Sep 17 00:00:00 2001
From: Bruce Hill <bruce@bruce-hill.com>
Date: Sun, 31 Aug 2025 23:33:22 -0400
Subject: Switch to using optional return values for list indexing.

---
 docs/lists.md | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

(limited to 'docs/lists.md')

diff --git a/docs/lists.md b/docs/lists.md
index dfb64aad..d12a0b5b 100644
--- a/docs/lists.md
+++ b/docs/lists.md
@@ -62,24 +62,23 @@ last item, `-2` is the second-to-last, and so on.
 ```tomo
 list := [10, 20, 30, 40]
 >> list[1]
-= 10
+= 10?
 
 >> list[2]
-= 20
+= 20?
+
+>> list[999]
+= none
 
 >> list[-1]
-= 40
+= 40?
 
 >> list[-2]
-= 30
+= 30?
 ```
 
 If a list index of `0` or any value larger than the length of the list is
-used, it will trigger a runtime error that will print what the invalid list
-index was, the length of the list, and a stack trace. As a performance
-operation, if list bounds checking proves to be a performance hot spot, you
-can explicitly disable bounds checking by adding `list[i; unchecked]` to the
-list access.
+used, a `none` value will be returned.
 
 ## Iteration
 
-- 
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