General Hashtable optimization

Perfect Hash tabel initial implementation
Table caching
Bug fixesw

server/hasher.h

@@ -162,7 +162,9 @@ struct PerfectHashTable {
 		
 	// }
 	template <typename ... Types, template <typename> class VT>
-	void construct(VT<Types>&... args) {
+	// std::enable_if_t<std::is_same_v<ValueType, bool>, void>
+	void
+	construct(VT<Types>&... args) { // construct a hash set
 		((this->n_cols = args.size), ...);
 		static_assert(
 			(sizeof...(Types) < PerfectHashingThreshold) &&
@@ -198,6 +200,6 @@ struct PerfectHashTable {
 			// problem: random memory access
 		}
 		// delete[] hash_values;
-		free(hash_values);
+		free(hash_values); // dispatch to gc
 	}
 };

server/vector_type.hpp

@@ -505,9 +505,16 @@ public:
 		ht_base =  static_cast<uint32_t *>(calloc(sz, sizeof(uint32_t)));
 	}
 
+	template<typename... Keys_t>
+	inline void hashtable_push_all(Keys_t& ... keys, uint32_t len) {
+		for(uint32_t i = 0; i < len; ++i) 
+			reversemap[i] = ankerl::unordered_dense::set<Key, Hash>::hashtable_push(keys[i]...);
+		for(uint32_t i = 0; i < len; ++i) 
+			++ht_base[reversemap[i]]; 
+	}
 	inline void hashtable_push(Key&& k, uint32_t i){
-		reversemap[i] = ankerl::unordered_dense::set<Key, Hash>::hashtable_push(std::move(k));
-		++ht_base[reversemap[i]];
+		reversemap[i] = ankerl::unordered_dense::set<Key, Hash>::hashtable_push(k);
+		++ht_base[reversemap[i]]; // do this seperately?
 	}
 
 	auto ht_postproc(uint32_t sz) {