docs: Documentation updated

docs/reference/core/concepts.rst

@@ -14,7 +14,7 @@ Concepts
 
 .. concept:: template<typename T> Prefix
 
-    A concept matching a symbol prefix. Satisfied by all instantiations of :class:`prefix`.
+    A concept matching a symbol prefix. Satisfied by all instantiations of :struct:`prefix`.
 
 .. concept:: template<ratio R> UnitRatio
 
@@ -71,13 +71,13 @@ Concepts
 .. concept:: template<typename T> QuantityValue
 
     A concept matching types that can be used as a `Quantity` representation type. Satisfied
-    by types that match :expr:`(!Quantity<T>) && (!QuantityLike<T>) && (!WrappedQuantity<T>) && std::regular<T>`
+    by types that match ``(!Quantity<T>) && (!QuantityLike<T>) && (!WrappedQuantity<T>) && std::regular<T>``
     and satisfy one of the following:
 
-    - if :expr:`common_type_with<T, std::intmax_t>` is ``true``, then :expr:`std::common_type_t<T, std::intmax_t>`
+    - if ``common_type_with<T, std::intmax_t>`` is ``true``, then ``std::common_type_t<T, std::intmax_t>``
       must at least provide binary multiplication and division operators,
-    - otherwise, :expr:`T::value_type` must be valid, :expr:`common_type_with<T::value_type, std::intmax_t>` be
-      ``true``, and :expr:`std::common_type_t<T::value_type, std::intmax_t>` must at least provide binary
+    - otherwise, ``T::value_type`` must be valid, ``common_type_with<T::value_type, std::intmax_t>`` be
+      ``true``, and ``std::common_type_t<T::value_type, std::intmax_t>`` must at least provide binary
       multiplication and division operators with itself and ``T``.
 
 .. concept:: template<typename T> QuantityPoint
@@ -85,6 +85,26 @@ Concepts
     A concept matching all quantity points in the library. Satisfied by all instantiations of
     :class:`quantity_point`.
 
+.. concept:: template<typename T> Kind
+
+    A concept matching all kind types. Satisfied by all kind types derived from an specialization of
+    :class:`kind`.
+
+.. concept:: template<typename T> PointKind
+
+    A concept matching all point kind types. Satisfied by all point kind types derived from an specialization of
+    :class:`point_kind`.
+
+.. concept:: template<typename T> QuantityKind
+
+    A concept matching all quantity kinds in the library. Satisfied by all specializations of
+    :class:`quantity_kind`.
+
+.. concept:: template<typename T> QuantityPointKind
+
+    A concept matching all quantity point kinds in the library. Satisfied by all specializations of
+    :class:`quantity_point_kind`.
+
 .. concept:: template<typename Dim, template<typename...> typename DimTemplate> DimensionOfT
 
     A concept matching all dimensions being the instantiations derived from the provided dimension
@@ -95,7 +115,44 @@ Concepts
     A concept matching all quantities with a dimension being the instantiation derived from
     the provided dimension class template.
 
-.. concept:: template<typename T, typename Dim> QuantityOf
+.. concept:: template<typename Q, typename Dim> QuantityOf
 
     A concept matching all quantities with a dimension being the instantiation derived from
     the provided dimension type.
+
+.. concept:: template<typename Q1, typename Q2> QuantityEquivalentTo
+
+    A concept matching two equivalent quantities. Satisfied by quantities having equivalent dimensions.
+
+.. concept:: template<typename QP, typename Dim> QuantityPointOf
+
+    A concept matching all quantity points with a dimension being the instantiation derived from
+    the provided dimension type.
+
+.. concept:: template<typename QP1, typename QP2> QuantityPointEquivalentTo
+
+    A concept matching two equivalent quantity points. Satisfied by quantity points having equivalent
+    dimensions.
+
+.. concept:: template<typename QK, typename K> QuantityKindOf
+
+    A concept matching only quantity kinds of a specific kind.
+
+    :tparam QK: Quantity kind to verify.
+    :tparam K: Kind type to use for verification.
+
+.. concept:: template<typename QK1, typename QK2> QuantityKindEquivalentTo
+
+    A concept matching two equivalent quantity kinds. Satisfied by quantity kinds having equivalent kinds.
+ 
+.. concept:: template<typename QPK, typename PK> QuantityPointKindOf
+ 
+    A concept matching only quantity point kinds of a specific point kind.
+ 
+    :tparam QPK: Quantity point kind to verify.
+    :tparam PK: Point kind type to use for verification.
+
+.. concept:: template<typename QPK1, typename QPK2> QuantityPointKindEquivalentTo
+
+    A concept matching two equivalent quantity point kinds. Satisfied by quantity point kinds having
+    equivalent kinds.

docs/reference/core/downcasting.rst

@@ -1,6 +1,8 @@
 The Downcasting Facility
 ========================
 
+.. doxygenenum:: downcast_mode
+
 .. concept:: template<typename T> Downcastable
 
 .. doxygenstruct:: units::downcast_base

docs/reference/core/types.rst

@@ -6,6 +6,9 @@ Types
 
     types/quantity
     types/quantity_point
+    types/kind
+    types/quantity_kind
+    types/quantity_point_kind
     types/dimensions
     types/units
     types/prefixes

docs/reference/core/types/kind.rst

@@ -0,0 +1,8 @@
+Kinds
+=====
+
+.. doxygenstruct:: units::kind
+   :members:
+
+.. doxygenstruct:: units::point_kind
+   :members:

docs/reference/core/types/quantity_kind.rst

@@ -0,0 +1,6 @@
+Quantity Kind
+=============
+
+.. doxygenclass:: units::quantity_kind
+   :members:
+   :undoc-members:

docs/reference/core/types/quantity_point_kind.rst

@@ -0,0 +1,6 @@
+Quantity Point Kind
+===================
+
+.. doxygenclass:: units::quantity_point_kind
+   :members:
+   :undoc-members: