diff --git a/doc/docs.md b/doc/docs.md
index 11642b1789..6ffde1293f 100644
--- a/doc/docs.md
+++ b/doc/docs.md
@@ -1773,7 +1773,7 @@ mut:
 
 fn (mut iter SquareIterator) next() ?int {
 	if iter.idx >= iter.arr.len {
-		return error('')
+		return none
 	}
 	defer {
 		iter.idx++