✨ cron

src/defer.rs

@@ -1,16 +1,22 @@
+use std::mem::take;
+
 pub struct Defer {
-    f: Box<dyn Fn()>,
+    f: Option<Box<dyn FnOnce()>>,
 }
 
 impl Defer {
-    pub fn new<F: Fn() + 'static>(f: F) -> Self {
-        Self { f: Box::new(f) }
+    pub fn new<F: FnOnce() + 'static>(f: F) -> Self {
+        Self {
+            f: Some(Box::new(f)),
+        }
     }
 }
 
 impl Drop for Defer {
     fn drop(&mut self) {
         log::debug!("Calling defer function");
-        self.f.as_ref()();
+        if let Some(f) = take(&mut self.f) {
+            f();
+        }
     }
 }