diff options
Diffstat (limited to 'shared/loki/HierarchyGenerators.h')
| -rw-r--r-- | shared/loki/HierarchyGenerators.h | 374 |
1 files changed, 187 insertions, 187 deletions
diff --git a/shared/loki/HierarchyGenerators.h b/shared/loki/HierarchyGenerators.h index 3fa11ffc..83ec194c 100644 --- a/shared/loki/HierarchyGenerators.h +++ b/shared/loki/HierarchyGenerators.h @@ -2,14 +2,14 @@ // The Loki Library // Copyright (c) 2001 by Andrei Alexandrescu // This code accompanies the book: -// Alexandrescu, Andrei. "Modern C++ Design: Generic Programming and Design +// Alexandrescu, Andrei. "Modern C++ Design: Generic Programming and Design // Patterns Applied". Copyright (c) 2001. Addison-Wesley. -// Permission to use, copy, modify, distribute and sell this software for any -// purpose is hereby granted without fee, provided that the above copyright -// notice appear in all copies and that both that copyright notice and this +// Permission to use, copy, modify, distribute and sell this software for any +// purpose is hereby granted without fee, provided that the above copyright +// notice appear in all copies and that both that copyright notice and this // permission notice appear in supporting documentation. -// The author or Addison-Wesley Longman make no representations about the -// suitability of this software for any purpose. It is provided "as is" +// The author or Addison-Wesley Longman make no representations about the +// suitability of this software for any purpose. It is provided "as is" // without express or implied warranty. //////////////////////////////////////////////////////////////////////////////// #ifndef LOKI_HIERARCHYGENERATORS_INC_ @@ -25,8 +25,8 @@ namespace Loki { #if defined(_MSC_VER) && _MSC_VER >= 1300 -#pragma warning( push ) - // 'class1' : base-class 'class2' is already a base-class of 'class3' +#pragma warning( push ) +// 'class1' : base-class 'class2' is already a base-class of 'class3' #pragma warning( disable : 4584 ) #endif // _MSC_VER @@ -35,180 +35,180 @@ namespace Loki // Generates a scattered hierarchy starting from a typelist and a template // Invocation (TList is a typelist, Unit is a template of one arg): // GenScatterHierarchy<TList, Unit> -// The generated class inherits all classes generated by instantiating the -// template 'Unit' with the types contained in TList +// The generated class inherits all classes generated by instantiating the +// template 'Unit' with the types contained in TList //////////////////////////////////////////////////////////////////////////////// - namespace Private - { - // The following type helps to overcome subtle flaw in the original - // implementation of GenScatterHierarchy. - // The flaw is revealed when the input type list of GenScatterHierarchy - // contains more then one element of the same type (e.g. LOKI_TYPELIST_2(int, int)). - // In this case GenScatterHierarchy will contain multiple bases of the same - // type and some of them will not be reachable (per 10.3). - // For example before the fix the first element of Tuple<LOKI_TYPELIST_2(int, int)> - // is not reachable in any way! - template<class, class> - struct ScatterHierarchyTag; - } +namespace Private +{ +// The following type helps to overcome subtle flaw in the original +// implementation of GenScatterHierarchy. +// The flaw is revealed when the input type list of GenScatterHierarchy +// contains more then one element of the same type (e.g. LOKI_TYPELIST_2(int, int)). +// In this case GenScatterHierarchy will contain multiple bases of the same +// type and some of them will not be reachable (per 10.3). +// For example before the fix the first element of Tuple<LOKI_TYPELIST_2(int, int)> +// is not reachable in any way! +template<class, class> +struct ScatterHierarchyTag; +} - template <class TList, template <class> class Unit> - class GenScatterHierarchy; - - template <class T1, class T2, template <class> class Unit> - class GenScatterHierarchy<Typelist<T1, T2>, Unit> - : public GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> - , public GenScatterHierarchy<T2, Unit> - { - public: - typedef Typelist<T1, T2> TList; - // Insure that LeftBase is unique and therefore reachable - typedef GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> LeftBase; - typedef GenScatterHierarchy<T2, Unit> RightBase; - template <typename T> struct Rebind - { - typedef Unit<T> Result; - }; - }; - - // In the middle *unique* class that resolve possible ambiguity - template <class T1, class T2, template <class> class Unit> - class GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> - : public GenScatterHierarchy<T1, Unit> +template <class TList, template <class> class Unit> +class GenScatterHierarchy; + +template <class T1, class T2, template <class> class Unit> +class GenScatterHierarchy<Typelist<T1, T2>, Unit> + : public GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> + , public GenScatterHierarchy<T2, Unit> +{ +public: + typedef Typelist<T1, T2> TList; + // Insure that LeftBase is unique and therefore reachable + typedef GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> LeftBase; + typedef GenScatterHierarchy<T2, Unit> RightBase; + template <typename T> struct Rebind { + typedef Unit<T> Result; }; +}; + +// In the middle *unique* class that resolve possible ambiguity +template <class T1, class T2, template <class> class Unit> +class GenScatterHierarchy<Private::ScatterHierarchyTag<T1, T2>, Unit> + : public GenScatterHierarchy<T1, Unit> +{ +}; - template <class AtomicType, template <class> class Unit> - class GenScatterHierarchy : public Unit<AtomicType> +template <class AtomicType, template <class> class Unit> +class GenScatterHierarchy : public Unit<AtomicType> +{ + typedef Unit<AtomicType> LeftBase; + template <typename T> struct Rebind { - typedef Unit<AtomicType> LeftBase; - template <typename T> struct Rebind - { - typedef Unit<T> Result; - }; + typedef Unit<T> Result; }; - - template <template <class> class Unit> - class GenScatterHierarchy<NullType, Unit> +}; + +template <template <class> class Unit> +class GenScatterHierarchy<NullType, Unit> +{ + template <typename T> struct Rebind { - template <typename T> struct Rebind - { - typedef Unit<T> Result; - }; + typedef Unit<T> Result; }; - +}; + //////////////////////////////////////////////////////////////////////////////// // function template Field // Accesses a field in an object of a type generated with GenScatterHierarchy // Invocation (obj is an object of a type H generated with GenScatterHierarchy, // T is a type in the typelist used to generate H): // Field<T>(obj) -// returns a reference to Unit<T>, where Unit is the template used to generate H +// returns a reference to Unit<T>, where Unit is the template used to generate H //////////////////////////////////////////////////////////////////////////////// - template <class T, class H> - typename H::template Rebind<T>::Result& Field(H& obj) - { - return obj; - } - - template <class T, class H> - const typename H::template Rebind<T>::Result& Field(const H& obj) - { - return obj; - } - +template <class T, class H> +typename H::template Rebind<T>::Result& Field(H& obj) +{ + return obj; +} + +template <class T, class H> +const typename H::template Rebind<T>::Result& Field(const H& obj) +{ + return obj; +} + //////////////////////////////////////////////////////////////////////////////// // function template TupleUnit -// The building block of tuples +// The building block of tuples //////////////////////////////////////////////////////////////////////////////// - template <class T> - struct TupleUnit - { - T value_; - operator T&() { return value_; } - operator const T&() const { return value_; } - }; +template <class T> +struct TupleUnit +{ + T value_; + operator T& () { return value_; } + operator const T& () const { return value_; } +}; //////////////////////////////////////////////////////////////////////////////// // class template Tuple -// Implements a tuple class that holds a number of values and provides field -// access to them via the Field function (below) +// Implements a tuple class that holds a number of values and provides field +// access to them via the Field function (below) //////////////////////////////////////////////////////////////////////////////// - template <class TList> - struct Tuple : public GenScatterHierarchy<TList, TupleUnit> - { - }; +template <class TList> +struct Tuple : public GenScatterHierarchy<TList, TupleUnit> +{ +}; //////////////////////////////////////////////////////////////////////////////// // helper class template FieldHelper // See Field below //////////////////////////////////////////////////////////////////////////////// - template <class H, unsigned int i> struct FieldHelper; - - template <class H> - struct FieldHelper<H, 0> +template <class H, unsigned int i> struct FieldHelper; + +template <class H> +struct FieldHelper<H, 0> +{ + typedef typename H::TList::Head ElementType; + typedef typename H::template Rebind<ElementType>::Result UnitType; + + enum { - typedef typename H::TList::Head ElementType; - typedef typename H::template Rebind<ElementType>::Result UnitType; - - enum - { - isTuple = Conversion<UnitType, TupleUnit<ElementType> >::sameType, - isConst = TypeTraits<H>::isConst - }; - - typedef const typename H::LeftBase ConstLeftBase; - - typedef typename Select<isConst, ConstLeftBase, + isTuple = Conversion<UnitType, TupleUnit<ElementType> >::sameType, + isConst = TypeTraits<H>::isConst + }; + + typedef const typename H::LeftBase ConstLeftBase; + + typedef typename Select<isConst, ConstLeftBase, typename H::LeftBase>::Result LeftBase; - - typedef typename Select<isTuple, ElementType, + + typedef typename Select<isTuple, ElementType, UnitType>::Result UnqualifiedResultType; - typedef typename Select<isConst, const UnqualifiedResultType, - UnqualifiedResultType>::Result ResultType; - - static ResultType& Do(H& obj) - { - LeftBase& leftBase = obj; - return leftBase; - } - }; + typedef typename Select<isConst, const UnqualifiedResultType, + UnqualifiedResultType>::Result ResultType; + + static ResultType& Do(H& obj) + { + LeftBase& leftBase = obj; + return leftBase; + } +}; + +template <class H, unsigned int i> +struct FieldHelper +{ + typedef typename TL::TypeAt<typename H::TList, i>::Result ElementType; + typedef typename H::template Rebind<ElementType>::Result UnitType; - template <class H, unsigned int i> - struct FieldHelper + enum { - typedef typename TL::TypeAt<typename H::TList, i>::Result ElementType; - typedef typename H::template Rebind<ElementType>::Result UnitType; - - enum - { - isTuple = Conversion<UnitType, TupleUnit<ElementType> >::sameType, - isConst = TypeTraits<H>::isConst - }; - - typedef const typename H::RightBase ConstRightBase; - - typedef typename Select<isConst, ConstRightBase, + isTuple = Conversion<UnitType, TupleUnit<ElementType> >::sameType, + isConst = TypeTraits<H>::isConst + }; + + typedef const typename H::RightBase ConstRightBase; + + typedef typename Select<isConst, ConstRightBase, typename H::RightBase>::Result RightBase; - typedef typename Select<isTuple, ElementType, + typedef typename Select<isTuple, ElementType, UnitType>::Result UnqualifiedResultType; - typedef typename Select<isConst, const UnqualifiedResultType, - UnqualifiedResultType>::Result ResultType; - - static ResultType& Do(H& obj) - { - RightBase& rightBase = obj; - return FieldHelper<RightBase, i - 1>::Do(rightBase); - } - }; + typedef typename Select<isConst, const UnqualifiedResultType, + UnqualifiedResultType>::Result ResultType; + + static ResultType& Do(H& obj) + { + RightBase& rightBase = obj; + return FieldHelper<RightBase, i - 1>::Do(rightBase); + } +}; //////////////////////////////////////////////////////////////////////////////// // function template Field @@ -217,23 +217,23 @@ namespace Loki // i is the index of a type in the typelist used to generate H): // Field<i>(obj) // returns a reference to Unit<T>, where Unit is the template used to generate H -// and T is the i-th type in the typelist +// and T is the i-th type in the typelist //////////////////////////////////////////////////////////////////////////////// - template <int i, class H> - typename FieldHelper<H, i>::ResultType& - Field(H& obj) - { - return FieldHelper<H, i>::Do(obj); - } - +template <int i, class H> +typename FieldHelper<H, i>::ResultType& +Field(H& obj) +{ + return FieldHelper<H, i>::Do(obj); +} + // template <int i, class H> // const typename FieldHelper<H, i>::ResultType& // Field(const H& obj) // { // return FieldHelper<H, i>::Do(obj); // } - + //////////////////////////////////////////////////////////////////////////////// // class template GenLinearHierarchy // Generates a linear hierarchy starting from a typelist and a template @@ -241,49 +241,49 @@ namespace Loki // GenScatterHierarchy<TList, Unit> //////////////////////////////////////////////////////////////////////////////// - template - < - class TList, - template <class AtomicType, class Base> class Unit, - class Root = EmptyType - > - class GenLinearHierarchy; - - template - < - class T1, - class T2, - template <class, class> class Unit, - class Root - > - class GenLinearHierarchy<Typelist<T1, T2>, Unit, Root> - : public Unit< T1, GenLinearHierarchy<T2, Unit, Root> > - { - }; +template +< +class TList, + template <class AtomicType, class Base> class Unit, + class Root = EmptyType + > +class GenLinearHierarchy; - template - < - class T, - template <class, class> class Unit, - class Root - > - class GenLinearHierarchy<Typelist<T, NullType>, Unit, Root> - : public Unit<T, Root> - { - }; +template +< +class T1, + class T2, + template <class, class> class Unit, + class Root + > +class GenLinearHierarchy<Typelist<T1, T2>, Unit, Root> + : public Unit< T1, GenLinearHierarchy<T2, Unit, Root> > +{ +}; - template - < - template <class, class> class Unit, - class Root - > - class GenLinearHierarchy<NullType , Unit, Root> - : public Root // is this better: Unit<NullType, Root> ? - { - }; +template +< +class T, + template <class, class> class Unit, + class Root + > +class GenLinearHierarchy<Typelist<T, NullType>, Unit, Root> + : public Unit<T, Root> +{ +}; + +template +< +template <class, class> class Unit, + class Root + > +class GenLinearHierarchy<NullType , Unit, Root> + : public Root // is this better: Unit<NullType, Root> ? +{ +}; #if defined(_MSC_VER) && _MSC_VER >= 1300 -#pragma warning( pop ) +#pragma warning( pop ) #endif } // namespace Loki |