testScalar

version(showAssertTags) dbg();
   testScalar!(8,
               bool,
               double, float,
               long, int, short, byte,
               ulong, uint, ushort, ubyte);

version(showAssertTags) dbg();
   alias Key = ubyte;
   auto set = RadixTreeSet!(Key, TestAllocator)();

   assert(!set.root);

   foreach (immutable i; 0 .. 7)
   {
       assert(!set.contains(i));
       assert(set.insert(i));
       assert(set.root.peek!HeptLeaf1);
   }

   foreach (immutable i; 7 .. 48)
   {
       assert(!set.contains(i));
       assert(set.insert(i));
       assert(set.root.peek!(SparseLeaf1!void*));
   }

   foreach (immutable i; 48 .. 256)
   {
       assert(!set.contains(i));
       assert(set.insert(i));
       assert(set.root.peek!(DenseLeaf1!void*));
   }