From 4f9e9d9a6e8305a4afc26de61114ad7a7ba920b5 Mon Sep 17 00:00:00 2001
From: luk3yx <luk3yx@users.noreply.github.com>
Date: Wed, 19 Feb 2025 12:01:35 +1300
Subject: [PATCH] Document on_quit as an experimental feature

---
 README.md | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/README.md b/README.md
index beecb1a..a6d5c5a 100644
--- a/README.md
+++ b/README.md
@@ -597,4 +597,29 @@ end)
 
 Special characters (excluding `-` and `_`) are not allowed in embed names.
 
+</details><details>
+<summary><b>Running code when a form is closed</b></summary>
+
+`gui.Container`, `gui.HBox`, `gui.VBox`, and `gui.Stack` elements support an
+`on_quit` callback which gets run when a player closes a form.
+
+Note that this function is not called in some cases, such as when the player
+leaves without closing the form or when another form/formspec is shown.
+
+This function must not return anything, behaviour may get added to return
+values in the future.
+
+```lua
+local parent_form = flow.make_gui(function(player, ctx)
+    return gui.VBox{
+        on_quit = function(player, ctx)
+            core.chat_send_player(player:get_player_name(), "Form closed!")
+        end,
+    }
+end)
+```
+
+If multiple `on_quit` callbacks are specified in different elements, they will
+all get called.
+
 </details>