From 636618e4ac4821f5c1c919239ef557c5f202abe4 Mon Sep 17 00:00:00 2001
From: Guy Korland <gkorland@gmail.com>
Date: Tue, 17 Dec 2019 17:47:46 +0200
Subject: [PATCH] fix #29 check for overflow

---
 src/select/mod.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/select/mod.rs b/src/select/mod.rs
index 56c4efe..e021b34 100644
--- a/src/select/mod.rs
+++ b/src/select/mod.rs
@@ -1058,7 +1058,7 @@ fn replace_value<F: FnMut(Value) -> Option<Value>>(
 ) {
     let mut target = value;
 
-    let last_index = tokens.len() - 1;
+    let last_index = tokens.len().checked_sub(1).unwrap_or(0);
     for (i, token) in tokens.drain(..).enumerate() {
         let target_once = target;
         let is_last = i == last_index;