issue/43 Computing deleted doc bitset

src/datastruct/stacker/hashmap.rs

@@ -125,6 +125,10 @@ impl<'a, V> HashMap<'a, V> where V: HeapAllocable {
             .map(move |addr: u32| heap.get_mut_ref::<V>(addr))
     }
 
+    pub fn heap(&self) -> &Heap {
+        &self.heap
+    }
+
     pub fn get_or_create<S: AsRef<[u8]>>(&mut self, key: S) -> &mut V {
         let entry = self.lookup(key.as_ref());
         match entry {

src/datastruct/stacker/heap.rs

@@ -41,7 +41,6 @@ impl Heap {
         self.inner().clear();
     }
     
-    
     /// Return the heap capacity.
     pub fn capacity(&self,) -> u32 {
         self.inner().capacity()
@@ -91,6 +90,10 @@ impl Heap {
     pub fn get_mut_ref<Item>(&self, addr: u32) -> &mut Item {
         self.inner().get_mut_ref(addr)
     }
+
+    pub fn get_ref<Item>(&self, addr: u32) -> &Item {
+        self.inner().get_mut_ref(addr)
+    }
 }