all: split reusable components into workspace crates

utils/src/stack.rs

@@ -0,0 +1,49 @@
+use {
+    crate::{
+        clonecell::UnsafeCellCloneSafe,
+        ptr_ext::{MutPtrExt, PtrExt},
+    },
+    std::{cell::UnsafeCell, mem},
+};
+
+pub struct Stack<T> {
+    vec: UnsafeCell<Vec<T>>,
+}
+
+impl<T> Default for Stack<T> {
+    fn default() -> Self {
+        Self {
+            vec: Default::default(),
+        }
+    }
+}
+
+impl<T> Stack<T> {
+    pub fn push(&self, v: T) {
+        unsafe {
+            self.vec.get().deref_mut().push(v);
+        }
+    }
+
+    pub fn pop(&self) -> Option<T> {
+        unsafe { self.vec.get().deref_mut().pop() }
+    }
+
+    pub fn to_vec(&self) -> Vec<T>
+    where
+        T: UnsafeCellCloneSafe,
+    {
+        unsafe {
+            let v = self.vec.get().deref();
+            (*v).clone()
+        }
+    }
+
+    pub fn take(&self) -> Vec<T> {
+        unsafe { mem::take(self.vec.get().deref_mut()) }
+    }
+
+    pub fn len(&self) -> usize {
+        unsafe { self.vec.get().deref().len() }
+    }
+}