Improve the Ponder API (#93)

- ponder::classes(), Class::functions(), & Class::properties().
- Add View class.

include/ponder/class.hpp

@@ -114,7 +114,7 @@ class PONDER_API Class : public Type
     Destructor m_destructor;        // Destructor (function able to delete an abstract object)
     UserObjectCreator m_userObjectCreator; // Convert pointer of class instance to UserObject
 
-public:     // declaration
+public: // declaration
 
     /**
      * \brief Declare a new metaclass
@@ -147,7 +147,10 @@ class PONDER_API Class : public Type
     template <typename T>
     static void undeclare();
 
-public:     // reflection
+public: // reflection
+
+    typedef View<const Function&, FunctionTable::const_iterator> FunctionView;
+    typedef View<const Property&, PropertyTable::const_iterator> PropertyView;
 
     /**
      * \brief Return the name of the metaclass
@@ -241,11 +244,11 @@ class PONDER_API Class : public Type
      * \return An iterator that can be used to iterator over all functions
      *
      * \code
-     * for (auto&& func : classByType<MyClass>().functionIterator())
+     * for (auto&& func : classByType<MyClass>().functions())
      *     foo(func.name(), func.value());
      * \endcode
      */
-    FunctionTable::Iterator functionIterator() const;
+    FunctionView functions() const;
 
     /**
      * \brief Look up a function by name and return success
@@ -303,11 +306,11 @@ class PONDER_API Class : public Type
      * \return An iterator that can be used to iterator over all properties
      *
      * \code
-     * for (auto&& prop : ponder::classByType<MyClass>().propertyIterator())
+     * for (auto&& prop : ponder::classByType<MyClass>())
      *     foo(prop.name(), prop.value());
      * \endcode
      */
-    PropertyTable::Iterator propertyIterator() const;
+    PropertyView properties() const;
 
     /**
      * \brief Look up a property by name and return success

include/ponder/class.inl

@@ -67,9 +67,9 @@ inline void Class::undeclare()
     detail::ClassManager::instance().removeClass(detail::getTypeId<T>());
 }
 
-inline Class::FunctionTable::Iterator Class::functionIterator() const
+inline Class::FunctionView Class::functions() const
 {
-    return m_functions.getIterator();
+    return FunctionView(m_functions.begin(), m_functions.end());
 }
 
 inline bool Class::tryFunction(const IdRef name, const Function *& funcRet) const
@@ -83,9 +83,9 @@ inline bool Class::tryFunction(const IdRef name, const Function *& funcRet) cons
     return false;
 }
 
-inline Class::PropertyTable::Iterator Class::propertyIterator() const
+inline Class::PropertyView Class::properties() const
 {
-    return m_properties.getIterator();
+    return PropertyView(m_properties.begin(), m_properties.end());
 }
 
 inline bool Class::tryProperty(const IdRef name, const Property *& propRet) const

include/ponder/classget.hpp

@@ -41,7 +41,7 @@
 #include <string>
 
 namespace ponder {
-    
+
 /**
  * \brief Get the total number of existing metaclasses
  *
@@ -57,9 +57,9 @@ size_t classCount();
  * \relates Class
  * \snippet inspect.cpp classIterator
  *
- * \return Class iterator: `pair<String, Class*>`
+ * \return ClassView
  */
-const detail::ClassManager& classIterator();
+detail::ClassManager::ClassView classes();
 
 /**
  * \brief Get a metaclass from its name

include/ponder/classget.inl

@@ -34,9 +34,9 @@ inline size_t classCount()
     return detail::ClassManager::instance().count();
 }
 
-inline const detail::ClassManager& classIterator()
+inline detail::ClassManager::ClassView classes()
 {
-    return detail::ClassManager::instance();
+    return detail::ClassManager::instance().getClasses();
 }
 
 inline const Class& classByName(IdRef name)

include/ponder/detail/classmanager.hpp

@@ -57,6 +57,8 @@ class PONDER_API ClassManager : public ObserverNotifier
 
 public:
 
+    typedef View<const Class&, ClassTable::const_iterator> ClassView;
+
     /**
      * \brief Get the unique instance of the class
      *
@@ -97,24 +99,6 @@ class PONDER_API ClassManager : public ObserverNotifier
      */
     size_t count() const;
 
-    /**
-     * \brief Begin iterator for iterating over contained classes
-     *
-     * \return An iterator
-     *
-     * \see classIterator()
-     */
-    ClassTable::const_iterator begin() const;
-
-    /**
-     * \brief End iterator for iterating over contained classes
-     *
-     * \return An iterator
-     *
-     * \see classIterator()
-     */
-    ClassTable::const_iterator end() const;
-
     /**
      * \brief Get a metaclass from a C++ type
      *
@@ -182,6 +166,8 @@ class PONDER_API ClassManager : public ObserverNotifier
      */
     ~ClassManager();
 
+    ClassView getClasses() const;
+
 private:
 
     ClassTable m_classes;   // Table storing classes indexed by their ID

include/ponder/detail/dictionary.hpp

@@ -81,19 +81,8 @@ class Dictionary
     typedef pair_t value_type;
     typedef typename container_t::const_iterator const_iterator;
 
-    const_iterator begin() const    { return m_contents.begin(); }
-    const_iterator end() const      { return m_contents.end(); }
-
-    class Iterator {
-        const_iterator m_begin, m_end;
-    public:
-        Iterator(const_iterator b, const_iterator e) : m_begin(b), m_end(e) {}
-        const_iterator begin() const    { return m_begin; }
-        const_iterator end() const      { return m_end; }
-    };
-
-    // Allow iteration of dictionary without exposing the API.
-    Iterator getIterator() const { return Iterator(begin(), end()); }
+    const_iterator begin() const    { return m_contents.cbegin(); }
+    const_iterator end() const      { return m_contents.cend(); }
 
     const_iterator findKey(KEY_REF key) const
     {

include/ponder/type.hpp

@@ -220,6 +220,56 @@ struct Parameter
 //};
 
 } // namespace policy
+
+template <typename T, typename IT>
+class ViewIterator
+{
+private:
+    IT m_iter;
+    class Holder
+    {
+        const T m_value;
+    public:
+        Holder(IT value) : m_value(value) {}
+        T operator*() { return m_value; }
+    };
+public:
+    typedef T value_type;
+    typedef std::ptrdiff_t difference_type;
+    typedef std::input_iterator_tag iterator_category;
+
+    explicit ViewIterator(IT value) : m_iter(value) {}
+    value_type operator*() const { return *m_iter->second; }
+    bool operator==(const ViewIterator& other) const { return m_iter == other.m_iter; }
+    bool operator!=(const ViewIterator& other) const { return !(*this == other); }
+    Holder operator++(int)
+    {
+        Holder ret(m_iter);
+        ++m_iter;
+        return ret;
+    }
+    ViewIterator& operator++()
+    {
+        ++m_iter;
+        return *this;
+    }
+};
+
+template <typename T, typename IT>
+class View
+{
+public:
+    typedef ViewIterator<T, IT> Iterator;
+
+    View(IT b, IT e) : m_begin(b), m_end(e) {}
+
+    Iterator begin() { return Iterator(m_begin); }
+    Iterator end() { return Iterator(m_end); }
+
+private:
+    IT m_begin, m_end;
+};
+
 } // namespace ponder
 
 #endif // PONDER_TYPE_HPP

src/classmanager.cpp

@@ -86,14 +86,9 @@ size_t ClassManager::count() const
     return m_classes.size();
 }
 
-ClassManager::ClassTable::const_iterator ClassManager::begin() const
+ClassManager::ClassView ClassManager::getClasses() const
 {
-    return m_classes.begin();
-}
-
-ClassManager::ClassTable::const_iterator ClassManager::end() const
-{
-    return m_classes.end();
+    return ClassView(m_classes.begin(), m_classes.end());
 }
 
 const Class* ClassManager::getByIdSafe(TypeId const& id) const

test/examples/userdata.cpp

@@ -70,11 +70,10 @@ static void test()
     std::cout << (help ? help->to<ponder::Id>() : "no help") << std::endl;
 
     // print functions and any help
-    for (auto const& it : cls.functionIterator())
+    for (auto const& fn : cls.functions())
     {
-        auto const& fn = it.second;
-        std::cout << "\t" << fn->name() << ": ";
-        help = ponder::userDataStore()->getValue(*fn, "help");
+        std::cout << "\t" << fn.name() << ": ";
+        help = ponder::userDataStore()->getValue(fn, "help");
         if (help)
             std::cout << (help ? help->to<ponder::Id>() : "no help") << std::endl;
     }    

test/ponder/class.cpp

@@ -300,9 +300,9 @@ TEST_CASE("Class metadata can be retrieved")
     SECTION("iteration")
     {
         size_t count = 0;
-        for (auto&& cls : ponder::classIterator())
+        for (const auto& cls : ponder::classes())
         {
-            (void) cls.second->name();
+            (void) cls.name();
             ++count;
         }
         REQUIRE(count == ponder::classCount());
@@ -362,7 +362,7 @@ TEST_CASE("Class members can be inspected")
     SECTION("can iterate over properties")
     {
         int index = 0;
-        for (auto&& prop : metaclass.propertyIterator())
+        for (const auto& prop : metaclass.properties())
         {
             switch (index++) {
                 case 0:
@@ -377,7 +377,7 @@ TEST_CASE("Class members can be inspected")
     SECTION("can iterate over functions")
     {
         int index = 0;
-        for (auto&& func : metaclass.functionIterator())
+        for (auto&& func : metaclass.functions())
         {
             switch (index++) {
                 case 0:

test/ponder/dictionary.cpp

@@ -105,7 +105,7 @@ TEST_CASE("Ponder has a dictionary")
     SECTION("can iterate over key,values")
     {
         int count = 0;
-        for (auto&& it : dict->getIterator())
+        for (const auto& it : *dict)
         {
             REQUIRE(dict->at(count)->name() == it.name());
             REQUIRE(dict->at(count)->value() == it.value());

test/ponder/userobject.cpp

@@ -464,12 +464,11 @@ TEST_CASE("User objects can be inspected and modified")
         ponder::UserObject userObject(&object);
 
         int index = 0;
-        for (auto&& prop : ponder::classByType<MyClass>().propertyIterator())
+        for (const auto& prop : ponder::classByType<MyClass>().properties())
         {
             switch (index) {
             case 0:
                 REQUIRE(prop.name() == ponder::String("p"));
-                REQUIRE(prop.value()->name() == ponder::String("p"));
                 break;
             default: ;
             }