Merge pull request #2 from andreiavrammsd/v0.2.0

V0.2.0

.clang-format

@@ -1,6 +1,6 @@
 BasedOnStyle: Google
 IndentWidth: 4
 Language: Cpp
-PointerAlignment: Right
+PointerAlignment: Left
 BreakBeforeBraces: Stroustrup
 ColumnLimit: 120

.github/workflows/cmake.yml

@@ -1,4 +1,4 @@
-name: build
+name: test
 
 on:
   push:
@@ -10,7 +10,7 @@ env:
   BUILD_TYPE: Release
 
 jobs:
-  build:
+  test:
     # The CMake configure and build commands are platform agnostic and should work equally
     # well on Windows or Mac.  You can convert this to a matrix build if you need
     # cross-platform coverage.

CMakeLists.txt

@@ -1,11 +1,10 @@
 cmake_minimum_required(VERSION 3.17)
 project(poly_map)
-set(PROJECT_VERSION 0.1.0)
+set(PROJECT_VERSION 0.2.0)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED YES)
 set(CXX_EXTENSIONS NO)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wpedantic -Werror --coverage -fsanitize=undefined")
 
 include_directories(include)
 

include/msd/poly_map.hpp

@@ -11,142 +11,23 @@
 
 namespace msd {
 
-template <typename... Keys>
-class poly_map {
-    static_assert(sizeof...(Keys) > 0, "no key type provided");
-
-    struct poly_map_element;
-
-   public:
-    /**
-     * Checked access by key.
-     *
-     * @tparam T Type of key.
-     *
-     * @param key Key to index map by.
-     *
-     * @return Map at given key.
-     *
-     * @throws std::out_of_range if key not found.
-     */
-    template <typename T>
-    [[nodiscard]] poly_map_element& at(const T& key)
-    {
-        return elements_.at(key);
-    }
-
-    /**
-     * Checked access by list of keys.
-     *
-     * @tparam T Type of first key.
-     * @tparam Ts Types of other keys.
-     *
-     * @param key First key to index map by.
-     * @param keys Other keys.
-     *
-     * @return Map at given key.
-     *
-     * @throws std::out_of_range if key not found.
-     */
-    template <typename T, typename... Ts>
-    [[nodiscard]] auto& at(const T& key, const Ts&... keys)
-    {
-        return elements_.at(key).at(keys...);
-    }
-
-    /**
-     * Checked access by key. Const overload.
-     *
-     * @tparam T Type of key.
-     *
-     * @param key Key to index map by.
-     *
-     * @return Map at given key.
-     *
-     * @throws std::out_of_range if key not found.
-     */
-    template <typename T, typename... Ts>
-    [[nodiscard]] auto& at(const T& key, const Ts&... keys) const
-    {
-        return const_cast<poly_map*>(this)->at(key, keys...);
-    }
-
+/**
+ * Map value
+ */
+struct poly_map_value {
     /**
-     * Unchecked access by key.
+     * Set value in map.
      *
-     * @tparam T Type of key.
+     * @param value Value to set.
      *
-     * @param key Key to index map by.
-     *
-     * @return Map at given key.
-     *
-     * @throws std::out_of_range if key not found.
+     * @throws std::bad_alloc or the exception thrown by the assigned value's constructor.
      */
     template <typename T>
-    auto& operator[](const T& key)
-    {
-        return elements_[key];
-    }
-
-    /**
-     * Iterate over map element by given visitor.
-     *
-     * @param visitor Visitor with overloads for keys types.
-     */
-    template <typename V>
-    void for_each(V&& visitor)
-    {
-        elements_.for_each(std::forward<V>(visitor));
-    }
-
-    /**
-     * Iterate over map element by given visitor. Const overload.
-     *
-     * @param visitor Visitor with overloads for keys types.
-     */
-    template <typename V>
-    void for_each(V&& visitor) const
+    void set(T&& value)
     {
-        const_cast<poly_map*>(this)->for_each(std::forward<V>(visitor));
+        value_ = std::forward<T>(value);
     }
 
-    /**
-     * Tests if map has no elements.
-     */
-    [[nodiscard]] bool empty() const noexcept { return elements_.empty(); }
-
-    /**
-     * Returns number of elements.
-     */
-    [[nodiscard]] std::size_t size() const noexcept { return elements_.size(); }
-
-    /**
-     * Removes elements from map.
-     */
-    void clear() noexcept { elements_.elements_.clear(); }
-
-    /**
-     * Tests if given path of keys is in map.
-     *
-     * @param key Key to search for.
-     * @param keys List of keys to search for.
-     */
-    template <typename T, typename... Ts>
-    [[nodiscard]] bool contains(const T& key, const Ts&... keys) const
-    {
-        return elements_.contains(key, keys...);
-    }
-
-   private:
-    poly_map_element elements_;
-};
-
-/**
- * Map value
- */
-struct poly_map_value {
-    std::any value_;
-
     /**
      * Get value from map.
      *
@@ -171,18 +52,20 @@ struct poly_map_value {
      * Tests if value has been set.
      */
     [[nodiscard]] bool empty() const noexcept { return !value_.has_value(); }
+
+   private:
+    std::any value_;
 };
 
 /**
- * Child map
+ * Polymorphic map
  *
- * @tparam Keys Types of keys.
+ * @tparam Key First type of key.
+ * @tparam Keys Other optional types of keys.
  */
-template <typename... Keys>
-struct poly_map<Keys...>::poly_map_element {
-    std::map<std::variant<Keys...>, poly_map_element> elements_;
-    poly_map_value value_;
-
+template <typename Key, typename... Keys>
+class poly_map {
+   public:
     /**
      * Assign value to map.
      *
@@ -193,16 +76,14 @@ struct poly_map<Keys...>::poly_map_element {
     template <typename T>
     auto& operator=(T&& v)
     {
-        value_.value_ = std::forward<T>(v);
+        value_.set(std::forward<T>(v));
 
         return *this;
     }
 
     /**
      * Checked access by key.
      *
-     * @tparam T Type of key.
-     *
      * @param key Key to index map by.
      *
      * @return Map at given key.
@@ -218,9 +99,6 @@ struct poly_map<Keys...>::poly_map_element {
     /**
      * Checked access by list of keys.
      *
-     * @tparam T Type of first key.
-     * @tparam Ts Types of other keys.
-     *
      * @param key First key to index map by.
      * @param keys Other keys.
      *
@@ -229,15 +107,28 @@ struct poly_map<Keys...>::poly_map_element {
      * @throws std::out_of_range if key not found.
      */
     template <typename T, typename... Ts>
-    [[nodiscard]] poly_map_element& at(const T& key, const Ts&... keys)
+    [[nodiscard]] poly_map& at(const T& key, const Ts&... keys)
     {
         return elements_.at(key).at(keys...);
     }
 
     /**
-     * Unchecked access by key.
+     * Checked access by key. Const overload.
      *
-     * @tparam T Type of key.
+     * @param key Key to index map by.
+     *
+     * @return Map at given key.
+     *
+     * @throws std::out_of_range if key not found.
+     */
+    template <typename T, typename... Ts>
+    [[nodiscard]] auto& at(const T& key, const Ts&... keys) const
+    {
+        return const_cast<poly_map*>(this)->at(key, keys...);
+    }
+
+    /**
+     * Unchecked access by key.
      *
      * @param key Key to index map by.
      *
@@ -295,7 +186,7 @@ struct poly_map<Keys...>::poly_map_element {
     template <typename V>
     void for_each(V&& visitor) const
     {
-        const_cast<poly_map_element*>(this)->for_each(std::forward<V>(visitor));
+        const_cast<poly_map*>(this)->for_each(std::forward<V>(visitor));
     }
 
     /**
@@ -330,7 +221,7 @@ struct poly_map<Keys...>::poly_map_element {
     template <typename T>
     [[nodiscard]] bool contains(const T& key) const
     {
-        return elements_.find(key) != elements_.end();
+        return elements_.find(key) != elements_.cend();
     }
 
     /**
@@ -348,6 +239,28 @@ struct poly_map<Keys...>::poly_map_element {
 
         return elements_.at(key).contains(keys...);
     }
+
+    /**
+     * Access map element at next level
+     *
+     * @pre Map must not be empty: !empty().
+     *
+     * @return Reference to map.
+     */
+    poly_map& map() noexcept { return elements_.begin()->second; }
+
+    /**
+     * Access map element at next level.  Const overload.
+     *
+     * @pre Map must not be empty: !empty().
+     *
+     * @return Const reference to map.
+     */
+    const poly_map& map() const noexcept { return elements_.cbegin()->second; }
+
+   private:
+    std::map<std::variant<Key, Keys...>, poly_map> elements_;
+    poly_map_value value_;
 };
 
 }  // namespace msd

tests/CMakeLists.txt

@@ -1,3 +1,5 @@
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wpedantic -Werror --coverage -fsanitize=undefined")
+
 # Testing framework
 include(FetchContent)
 if (NOT googletest_POPULATED)

tests/poly_map_test.cpp

@@ -316,3 +316,40 @@ TEST_F(PolyMapTest, contains)
     EXPECT_FALSE(const_map.at(1).at(2).contains(2));
     EXPECT_TRUE(const_map.at(1).at(2).contains(3.1, 4.2));
 }
+
+template <typename T>
+bool recursive_find(poly_map_type& m, const T& value)
+{
+    if (m.contains(value)) {
+        return true;
+    }
+
+    if (m.empty()) {
+        return false;
+    }
+
+    return recursive_find(m.map(), value);
+}
+
+template <typename T>
+bool recursive_find(const poly_map_type& m, const T& value)
+{
+    if (m.contains(value)) {
+        return true;
+    }
+
+    if (m.empty()) {
+        return false;
+    }
+
+    return recursive_find(m.map(), value);
+}
+
+TEST_F(PolyMapTest, recursion)
+{
+    EXPECT_TRUE(recursive_find(map, "f"));
+    EXPECT_FALSE(recursive_find(map, 1.1));
+
+    EXPECT_TRUE(recursive_find(const_map, "f"));
+    EXPECT_FALSE(recursive_find(const_map, 1.1));
+}