Renamed function and class for loadinng the saved Annoy types.

Also moved the source code out of utils as it is only required for loading.

Also fixed the header to avoid infinitely recursive includes.

Author: LTLA

include/knncolle_annoy/load_annoy_prebuilt.hpp

@@ -2,7 +2,7 @@
 #define KNNCOLLE_ANNOY_LOAD_PREBUILT_HPP
 
 #include "utils.hpp"
-#include "knncolle_annoy.hpp"
+#include "Annoy.hpp"
 
 #include <cstddef>
 #include <stdexcept>
@@ -17,11 +17,52 @@
 
 namespace knncolle_annoy {
 
+/**
+ * @brief Template types of a saved Annoy index.
+ *
+ * Instances are typically created by `load_annoy_prebuilt_types()`.
+ */
+struct AnnoyPrebuiltTypes {
+    /**
+     * Type of the index, i.e., `AnnoyIndex_` in `AnnoyBuilder()`.
+     */
+    NumericType index;
+
+    /**
+     * Type of the data, i.e., `AnnoyData_` in `AnnoyBuilder()`.
+     */
+    NumericType data;
+
+    /**
+     * Name of the distance metric, i.e., `AnnoyDistance_` in `AnnoyBuilder()`.
+     */
+    std::string distance;
+};
+
+/**
+ * @param prefix Prefix of the file paths in which a prebuilt Annoy index was saved.
+ * An Annoy index is typically saved by calling the `knncolle::Prebuilt::save()` method of the Annoy subclass instance.
+ *
+ * @return Template types of the saved instance of a `knncolle::Prebuilt` Annoy subclass.
+ * This is typically used to choose template parameters for `load_annoy_prebuilt()`.
+ */
+inline AnnoyPrebuiltTypes load_annoy_prebuilt_types(const std::string& prefix) {
+    NumericType types[2];
+    knncolle::quick_load(prefix + "types", types, 2);
+
+    AnnoyPrebuiltTypes config;
+    config.index = types[0];
+    config.data = types[1];
+    config.distance = knncolle::quick_load_as_string(prefix + "distance");
+
+    return config;
+}
+
 /**
  * Helper function to define a `knncolle::LoadPrebuiltFunction` for Annoy in `knncolle::load_prebuilt()`.
  *
  * In an Annoy-specific `knncolle::LoadPrebuiltFunction`,
- * users should first call `scan_prebuilt_save_config()` to figure out the saved index's `AnnoyDistance_`, `AnnoyIndex` and `AnnoyData_`.
+ * users should first call `load_annoy_prebuilt_types()` to figure out the saved index's `AnnoyDistance_`, `AnnoyIndex` and `AnnoyData_`.
  * Then, they can call `load_annoy_prebuilt()` with the specified types to return a pointer to a `knncolle::Prebuilt` object.
  * This can be registered in `load_prebuilt_registry()` with the key in `knncolle_annoy::save_name`.
  * 

include/knncolle_annoy/utils.hpp

@@ -186,47 +186,6 @@ NumericType get_numeric_type() {
     return NumericType::UNKNOWN;
 }
 
-/**
- * @brief Configuration of a saved Annoy index.
- *
- * Instances are typically created by `scan_prebuilt_save_config()`.
- */
-struct PrebuiltSaveConfig {
-    /**
-     * Type of the index, i.e., `AnnoyIndex_` in `AnnoyBuilder()`.
-     */
-    NumericType index;
-
-    /**
-     * Type of the index, i.e., `AnnoyData_` in `AnnoyBuilder()`.
-     */
-    NumericType data;
-
-    /**
-     * Name of the distance metric, i.e., `AnnoyDistance_` in `AnnoyBuilder()`.
-     */
-    std::string distance;
-};
-
-/**
- * @param prefix Prefix of the file paths in which a prebuilt Annoy index was saved.
- * An Annoy index is typically saved by calling the `knncolle::Prebuilt::save()` method of the Annoy subclass instance.
- *
- * @return Configuration of the saved instance of a `knncolle::Prebuilt` Annoy subclass.
- * This is typically used to choose template parameters for `load_annoy_prebuilt()`.
- */
-inline PrebuiltSaveConfig scan_prebuilt_save_config(const std::string& prefix) {
-    NumericType types[2];
-    knncolle::quick_load(prefix + "types", types, 2);
-
-    PrebuiltSaveConfig config;
-    config.index = types[0];
-    config.data = types[1];
-    config.distance = knncolle::quick_load_as_string(prefix + "distance");
-
-    return config;
-}
-
 /**
  * Define a customized saving function to preserve type information from the Annoy index in `knncolle::Prebuilt::save()`.
  * Users can provide their own function here, to handle types that are unknown to `get_numeric_type()` or `get_distance_name()`.

tests/src/load_annoy_prebuilt.cpp

@@ -23,7 +23,7 @@ class AnnoyLoadPrebuiltTest : public TestCore, public ::testing::Test {
 
         auto& reg = knncolle::load_prebuilt_registry<int, double, double>();
         reg[knncolle_annoy::save_name] = [](const std::string& prefix) -> knncolle::Prebuilt<int, double, double>* {
-            auto scanned = knncolle_annoy::scan_prebuilt_save_config(prefix);
+            auto scanned = knncolle_annoy::load_annoy_prebuilt_types(prefix);
             if (std::strcmp(scanned.distance.c_str(), "euclidean") == 0) {
                 return knncolle_annoy::load_annoy_prebuilt<int, double, double, Annoy::Euclidean>(prefix);
             }