From 844f8217cae333f8f521f6e294b172d367db3499 Mon Sep 17 00:00:00 2001
From: adamritter <58403584+adamritter@users.noreply.github.com>
Date: Sun, 30 Oct 2022 13:15:01 +0000
Subject: [PATCH] Add replace_object_with that can pass an object without using
 mutable reference. This makes it possible to change an object in place and
 reuse it.

---
 src/signal/mutable.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/signal/mutable.rs b/src/signal/mutable.rs
index 37b3c08..44a4fce 100644
--- a/src/signal/mutable.rs
+++ b/src/signal/mutable.rs
@@ -239,6 +239,17 @@ impl<A> fmt::Debug for ReadOnlyMutable<A> where A: fmt::Debug {
 #[repr(transparent)]
 pub struct Mutable<A>(ReadOnlyMutable<A>);
 
+impl<A:Default> Mutable<A> {
+    pub fn replace_object_with<F>(&self, f: F) where F: FnOnce(A) -> A {
+        let mut state = self.state().lock.write().unwrap();
+        let old_value=std::mem::take(&mut state.value);
+        let new_value = f(old_value);
+        state.value=new_value;
+        
+        state.notify(true);
+    }
+}
+
 impl<A> Mutable<A> {
     // TODO should this inline ?
     pub fn new(value: A) -> Self {