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src/data_structures/circular_buffer.rs

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+use core::mem::MaybeUninit;
+
+#[derive(Debug)]
+pub struct CircularBuffer<T, const SIZE: usize> {
+    buffer: [MaybeUninit<T>; SIZE],
+    head: usize,
+    tail: usize,
+    len: usize,
+}
+
+impl<T, const SIZE: usize> CircularBuffer<T, SIZE> {
+    pub const fn new() -> Self {
+        Self {
+            buffer: [const { MaybeUninit::uninit() }; SIZE],
+            head: 0,
+            tail: 0,
+            len: 0,
+        }
+    }
+
+    pub fn len(&self) -> usize {
+        self.len
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    pub fn is_full(&self) -> bool {
+        self.len() == SIZE - 1
+    }
+
+    pub fn pop(&mut self) -> Option<T> {
+        if self.is_empty() {
+            None
+        } else {
+            let out = core::mem::replace(&mut self.buffer[self.head], MaybeUninit::uninit());
+            self.head = (self.head + 1) % SIZE;
+            self.len -= 1;
+            // # Safety
+            // the queue is not empty and head points to a valid value
+            Some(unsafe { out.assume_init() })
+        }
+    }
+
+    pub fn push(&mut self, value: T) {
+        self.buffer[self.tail] = MaybeUninit::new(value);
+        if self.is_full() {
+            self.head = (self.head + 1) % SIZE;
+        } else {
+            self.len += 1;
+        }
+        self.tail = (self.tail + 1) % SIZE;
+    }
+}