From 12e8e31bb2891f83cda666d5c689cca6f5bfef7e Mon Sep 17 00:00:00 2001
From: Ruofan XU <47302112+SleepyRoy@users.noreply.github.com>
Date: Fri, 5 Feb 2021 23:45:20 +0800
Subject: [PATCH] doc: document `!in` (#8546)

---
 doc/docs.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/doc/docs.md b/doc/docs.md
index 05aa69c27b..9ea863f530 100644
--- a/doc/docs.md
+++ b/doc/docs.md
@@ -1046,15 +1046,18 @@ match mut x {
 ### In operator
 
 `in` allows to check whether an array or a map contains an element.
+To do the opposite, use `!in`.
 
 ```v
 nums := [1, 2, 3]
 println(1 in nums) // true
+println(4 !in nums) // true
 m := {
 	'one': 1
 	'two': 2
 }
 println('one' in m) // true
+println('three' !in m) // true
 ```
 
 It's also useful for writing boolean expressions that are clearer and more compact: