Add enum_base::ssize()

- Add method to query the number of enumerators as sized integer

- Add documentation and tests for both size() and ssize()

README.rst

@@ -22,6 +22,7 @@ They can be iterated:
 
 .. code-block:: c++
 
+   std::cout << "Listing " << Status::size() << " enumerators:\n";
    for (const auto status : Status::all()) {
        std::cout << status.value() << "\n";
    }

cxx/include/enhanced_enum/enhanced_enum.hh

@@ -58,6 +58,15 @@ struct enum_base {
         return EnhancedEnum::values.size();
     }
 
+    /** \brief Get the number of enumerators as signed number
+     *
+     * \return The number of enumerators in this enum
+     */
+    static constexpr std::ptrdiff_t ssize() noexcept
+    {
+        return static_cast<std::ptrdiff_t>(size());
+    }
+
     /** \brief Get range over all enumerators
      *
      * \return A random accessible range containing all enumerators in

cxx/tests/test.cc

@@ -38,8 +38,10 @@ static_assert( enhanced_enum::is_label_enum_v<StatusLabel> );
 static_assert( std::is_same_v<enhanced_enum::make_enhanced_t<StatusLabel>, EnhancedStatus> );
 static_assert( std::is_same_v<enhanced_enum::make_enhanced_t<EnhancedStatus>, EnhancedStatus> );
 
-// enhance(), .get() and .value(), .from() are constexpr
+// Basic functions
 
+static_assert( EnhancedStatus::size() == 3u );
+static_assert( EnhancedStatus::ssize() == 3 );
 static_assert( enhance(StatusLabel::BUSY).get() == StatusLabel::BUSY );
 static_assert( enhance(StatusLabel::BUSY).value() == Statuses::BUSY_VALUE );
 static_assert( EnhancedStatus::from(Statuses::BUSY_VALUE) == Statuses::BUSY );

docs/enhancedenumlib.rst

@@ -241,8 +241,12 @@ deliberately explicit.
    static_assert( Statuses::INITIALIZING.get() == StatusLabel::INITIALIZING )
    static_assert( static_cast<StatusLabel>(Statuses::INITIALIZING) == StatusLabel::INITIALIZING );
 
-Iterating over enumerators
-..........................
+Enumerators as range
+....................
+
+The number of enumerators in an enhanced enum type can be queries by
+using the :cpp:func:`size()` and :cpp:func:`ssize()`, for unsigned and
+signed sizes, respectively.
 
 A range containing all enumerators of a given enum type can be
 constructed with the static :cpp:func:`all()` method: