libluna: Allow constructing a Slice from another one with a different pointer type

libluna/include/luna/Slice.h

@@ -11,6 +11,10 @@ template <typename T> class Slice
     {
     }
 
+    template <typename Tp> Slice(const Slice<Tp>& other) : m_data((T*)other.m_data), m_size(other.m_size)
+    {
+    }
+
     const T* data() const
     {
         return m_data;
@@ -46,6 +50,18 @@ template <typename T> class Slice
         return m_data + m_size;
     }
 
+    const T& operator[](usize index) const
+    {
+        check(index < m_size);
+        return m_data[index];
+    }
+
+    T& operator[](usize index)
+    {
+        check(index < m_size);
+        return m_data[index];
+    }
+
   private:
     T* const m_data;
     const usize m_size;