Implement Set Range

source/tanya/container/entry.d

@@ -12,6 +12,7 @@
  */
 module tanya.container.entry;
 
+import std.traits;
 import tanya.typecons;
 
 package struct SEntry(T)
@@ -63,14 +64,17 @@ package struct Bucket(T)
         this.status = BucketStatus.used;
     }
 
-    @property ref T content()
+    @property ref inout(T) content() inout
     {
         return this.content_;
     }
 
     void remove()
     {
-        this.content = T.init;
+        static if (hasElaborateDestructor!T)
+        {
+            destroy(this.content);
+        }
         this.status = BucketStatus.deleted;
     }
 

source/tanya/container/set.d

@@ -27,15 +27,112 @@ import tanya.memory;
  */
 struct Range(E)
 {
-    private alias ContainerType = CopyConstness!(E, Array!(Bucket!(Unqual!E)));
+    static if (isMutable!E)
-    private ContainerType* container;
+    {
+        private alias DataRange = Array!(Bucket!(Unqual!E)).Range;
+    }
+    else
+    {
+        private alias DataRange = Array!(Bucket!(Unqual!E)).ConstRange;
+    }
+    private DataRange dataRange;
 
     @disable this();
 
+    private this(DataRange dataRange)
+    {
+        while (!dataRange.empty && dataRange.front.status != BucketStatus.used)
+        {
+            dataRange.popFront();
+        }
+        while (!dataRange.empty && dataRange.back.status != BucketStatus.used)
+        {
+            dataRange.popBack();
+        }
+        this.dataRange = dataRange;
+    }
+
     @property Range save()
     {
         return this;
     }
+
+    @property bool empty() const
+    {
+        return this.dataRange.empty();
+    }
+
+    @property void popFront()
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.front.status == BucketStatus.used);
+    }
+    out
+    {
+        assert(this.dataRange.empty
+            || this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        do
+        {
+            dataRange.popFront();
+        }
+        while (!dataRange.empty && dataRange.front.status != BucketStatus.used);
+    }
+
+    @property void popBack()
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.back.status == BucketStatus.used);
+    }
+    out
+    {
+        assert(this.dataRange.empty
+            || this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        do
+        {
+            dataRange.popBack();
+        }
+        while (!dataRange.empty && dataRange.back.status != BucketStatus.used);
+    }
+
+    @property ref inout(E) front() inout
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.front.status == BucketStatus.used);
+    }
+    body
+    {
+        return dataRange.front.content;
+    }
+
+    @property ref inout(E) back() inout
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        return dataRange.back.content;
+    }
+
+    Range opIndex()
+    {
+        return typeof(return)(this.dataRange[]);
+    }
+
+    Range!(const E) opIndex() const
+    {
+        return typeof(return)(this.dataRange[]);
+    }
 }
 
 /**
@@ -95,6 +192,24 @@ struct Set(T)
         return this.data.length;
     }
 
+    /**
+     * Iterates over the $(D_PSYMBOL Set) and counts the elements.
+     *
+     * Returns: Count of elements within the $(D_PSYMBOL Set).
+     */
+    @property size_t length() const
+    {
+        size_t count;
+        foreach (ref e; this.data[])
+        {
+            if (e.status == BucketStatus.used)
+            {
+                ++count;
+            }
+        }
+        return count;
+    }
+
     private static const size_t[41] primes = [
         3, 7, 13, 23, 29, 37, 53, 71, 97, 131, 163, 193, 239, 293, 389, 521,
         769, 919, 1103, 1327, 1543, 2333, 3079, 4861, 6151, 12289, 24593,
@@ -229,6 +344,21 @@ struct Set(T)
     private DataType data;
     private size_t lengthIndex;
 
+    /**
+     * Returns: A bidirectional range that iterates over the $(D_PSYMBOL Set)'s
+     *          elements.
+     */
+    Range opIndex()
+    {
+        return typeof(return)(data[]);
+    }
+
+    /// Ditto.
+    ConstRange opIndex() const
+    {
+        return typeof(return)(data[]);
+    }
+
     mixin DefaultAllocator;
 }
 
@@ -269,3 +399,15 @@ private unittest
     assert(set.data[3].content == 16);
     assert(set.data[4].status == BucketStatus.empty);
 }
+
+// Static checks.
+private unittest
+{
+    import std.range.primitives;
+
+    static assert(isBidirectionalRange!(Set!int.ConstRange));
+    static assert(isBidirectionalRange!(Set!int.Range));
+
+    static assert(!isInfinite!(Set!int.Range));
+    static assert(!hasLength!(Set!int.Range));
+}