autocommit 2022-01-02 15:13:33 CET

src/utils/numcell.rs

@@ -0,0 +1,38 @@
+use std::cell::Cell;
+use std::ops::{Add, Sub};
+
+#[derive(Default)]
+pub struct NumCell<T> {
+    t: Cell<T>,
+}
+
+impl<T> NumCell<T> {
+    pub fn new(t: T) -> Self {
+        Self { t: Cell::new(t) }
+    }
+
+    pub fn load(&self) -> T
+    where
+        T: Copy,
+    {
+        self.t.get()
+    }
+
+    pub fn fetch_add(&self, n: T) -> T
+    where
+        T: Copy + Add<T, Output = T>,
+    {
+        let res = self.t.get();
+        self.t.set(res + n);
+        res
+    }
+
+    pub fn fetch_sub(&self, n: T) -> T
+    where
+        T: Copy + Sub<T, Output = T>,
+    {
+        let res = self.t.get();
+        self.t.set(res - n);
+        res
+    }
+}