Add a Queue type (which just wraps deque) #so

src/mango/util/collection/mod.rs

@@ -0,0 +1,2 @@
+pub mod queue;
+pub use self::queue::Queue;

src/mango/util/collection/queue.rs

@@ -0,0 +1,23 @@
+use std::collections::VecDeque;
+
+/// A one-ended queue.
+/// This is just a wrapper around deque so nobody pushes or pops the wrong end.
+pub struct Queue<T> {
+    deque: VecDeque<T>,
+}
+
+impl<T> Queue<T> {
+    pub fn new() -> Self {
+        Queue {
+            deque: VecDeque::with_capacity(16),
+        }
+    }
+
+    pub fn push(&mut self, value: T) {
+        self.deque.push_back(value)
+    }
+
+    pub fn pop(&mut self) -> Option<T> {
+        self.deque.pop_front()
+    }
+}

src/mango/util/mod.rs

@@ -1,3 +1,5 @@
+pub mod collection;
+
 pub mod strtype;
 
 pub mod numtype;