Interface update (#5)

* Query Interface Adjustments/Refactoring

Began the process of adjusting the query interface (and also the shard
interface, to a lesser degree) to better accommodate the user. In
particular the following changes have been made,

    1. The number of necessary template arguments for the query type
       has been drastically reduced, while also removing the void pointers
       and manual delete functions from the interface.

       This was accomplished by requiring many of the sub-types associated
       with a query (parameters, etc.) to be nested inside the main query
       class, and by forcing the SHARD type to expose its associated
       record type.

    2. User-defined query return types are now supported.

       Queries no longer are required to return strictly sets of records.
       Instead, the query now has LocalResultType and ResultType
       template parameters (which can be defaulted using a typedef in
       the Query type itself), allowing much more flexibility.

       Note that, at least for the short term, the LocalResultType must
       still expose the same is_deleted/is_tombstone interface as a
       Wrapped<R> used to, as this is currently needed for delete
       filtering. A better approach to this is, hopefully, forthcoming.

    3. Updated the ISAMTree.h shard and rangequery.h query to use the
       new interfaces, and adjusted the associated unit tests as well.

    4. Dropped the unnecessary "get_data()" function from the ShardInterface
       concept.

    5. Dropped the need to specify a record type in the ShardInterface
       concept. This is now handled using a required Shard::RECORD
       member of the Shard class itself, which should expose the name
       of the record type.

* Updates to framework to support new Query/Shard interfaces

Pretty extensive adjustments to the framework, particularly to the
templates themselves, along with some type-renaming work, to support
the new query and shard interfaces.

Adjusted the external query interface to take an rvalue reference, rather
than a pointer, to the query parameters.

* Removed framework-level delete filtering

This was causing some issues with the new query interface, and should
probably be reworked anyway, so I'm temporarily (TM) removing the
feature.

* Updated benchmarks + remaining code for new interface

1 files changed, 49 insertions, 17 deletions

diff --git a/include/framework/interface/Shard.h b/include/framework/interface/Shard.h
index c4a9180..bd980c0 100644
--- a/include/framework/interface/Shard.h
+++ b/include/framework/interface/Shard.h
@@ -1,7 +1,7 @@
 /*
  * include/framework/interface/Shard.h
  *
- * Copyright (C) 2023 Douglas B. Rumbaugh <drumbaugh@psu.edu> 
+ * Copyright (C) 2023-2024 Douglas B. Rumbaugh <drumbaugh@psu.edu>
  *
  * Distributed under the Modified BSD License.
  *
@@ -12,25 +12,57 @@
 
 namespace de {
 
-template <typename S, typename R>
-concept ShardInterface = RecordInterface<R> && requires(S s, std::vector<S*> spp, void *p, bool b, size_t i, BufferView<R> bv, R r) {
-    {S(spp)};
-    {S(std::move(bv))};
+template <typename SHARD>
+concept ShardInterface = RecordInterface<typename SHARD::RECORD> &&
+    requires(SHARD shard, const std::vector<SHARD *> &shard_vector, bool b,
+             BufferView<typename SHARD::RECORD> bv,
+             typename SHARD::RECORD rec) {
+  /* construct a shard from a vector of shards of the same type */
+  {SHARD(shard_vector)};
 
-    {s.point_lookup(r, b) } -> std::same_as<Wrapped<R>*>;
-    {s.get_data()} -> std::same_as<Wrapped<R>*>;
+  /* construct a shard from a buffer view (i.e., unsorted array of records) */
+  {SHARD(std::move(bv))};
+
+  /* perform a lookup for a record matching rec and return a pointer to it */
+  {
+    shard.point_lookup(rec, b)
+    } -> std::same_as<Wrapped<typename SHARD::RECORD> *>;
+
+  /*
+   * return the number of records in the shard -- used to determine when
+   * reconstructions occur
+   */
+  { shard.get_record_count() } -> std::convertible_to<size_t>;
+
+  /*
+   * return the number of tombstones in the shard -- can simply return
+   * 0 if tombstones are not in use.
+   */
+  { shard.get_tombstone_count() } -> std::convertible_to<size_t>;
+
+  /*
+   * return the number of bytes of memory used by the main data structure
+   * within the shard -- informational use only at the moment
+   */
+  { shard.get_memory_usage() } -> std::convertible_to<size_t>;
+
+  /*
+   * return the number of bytes of memory used by auxilliary data
+   * structures (bloom filters, etc.) within the shard -- informational
+   * use only at the moment
+   */
+  { shard.get_aux_memory_usage() } -> std::convertible_to<size_t>;
 
-    {s.get_record_count()} -> std::convertible_to<size_t>;
-    {s.get_tombstone_count()} -> std::convertible_to<size_t>;
-    {s.get_memory_usage()} -> std::convertible_to<size_t>;
-    {s.get_aux_memory_usage()} -> std::convertible_to<size_t>;
 };
 
-template <typename S, typename R>
-concept SortedShardInterface = ShardInterface<S, R> && requires(S s, R r, R *rp, size_t i) {
-    {s.lower_bound(r)} -> std::convertible_to<size_t>;
-    {s.upper_bound(r)} -> std::convertible_to<size_t>;
-    {s.get_record_at(i)} -> std::same_as<Wrapped<R>*>;
+template <typename SHARD>
+concept SortedShardInterface = ShardInterface<SHARD> &&
+    requires(SHARD shard, typename SHARD::RECORD rec, size_t index) {
+  { shard.lower_bound(rec) } -> std::convertible_to<size_t>;
+  { shard.upper_bound(rec) } -> std::convertible_to<size_t>;
+  {
+    shard.get_record_at(index)
+    } -> std::same_as<Wrapped<typename SHARD::RECORD> *>;
 };
 
-}
+} // namespace de