代码看起来很直接，没有前面宏定义那么复杂。但头文件的相互包括比较复杂。
如果仅仅是利用VS助手来寻找代码，出错的可能性非常之大。
对于模板元的调试非常的特殊。正确的代码是不能调试的，而是故意把它写错:比如，
vector1只能存放一个元素，那么故意写成两个元素，超出了界限，编译器自然会报错。
这样可以知道编译器调用的是什么地方的代码了。否则调用的是什么地方的代码都不知道（花了大量的时间来寻找代码）。
有些模板仅仅是声明没有定义。这样只是起一个标记作用，用类型来标记。这个vector同那个vector是不同的。比如：vector_tag<1>和vector_tag<2>就是不同，他们代表不同的类型。它的差异仅仅用类型就可以做到。网上仅有一篇博客说是定义，这儿显然是不对。如果是定义可以生成对像，我试了aux::vector_tag不能生成对像。
// Copyright Aleksey Gurtovoy 2000-2004
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// Preprocessed version of "boost/mpl/vector/vector10.hpp" header
// -- DO NOT modify by hand!
# define BOOST_MPL_AUX_NTTP_DECL(T, x) T x /**/
struct v_iter_tag;//仅仅是一个标志
struct integral_c_tag { BOOST_STATIC_CONSTANT(int, value = 0); };
template< int N>
struct int_
{
enum { value = N };
typedef int type;
typedef int_ value_type;
typedef integral_c_tag tag;
typedef int_ next;
typedef int_ prior;
// enables uniform function call syntax for families of overloaded
// functions that return objects of both arithmetic ('int', 'long',
// 'double', etc.) and wrapped integral types (for an example, see
// "mpl/example/power.cpp")
operator int() const { return static_cast(this->value); }
};
namespace boost { namespace mpl {
//起标记作用。同STL的代码这点来说很相似。
struct forward_iterator_tag : int_<0> { typedef forward_iterator_tag type; };
struct bidirectional_iterator_tag : int_<1> { typedef bidirectional_iterator_tag type; };
struct random_access_iterator_tag : int_<2> { typedef random_access_iterator_tag type; };
}}
# define BOOST_MPL_AUX_COMMON_NAME_WKND(name) /**/
#define BOOST_MPL_AUX_NA_PARAM(param) param = na
namespace boost { namespace mpl {
BOOST_MPL_AUX_COMMON_NAME_WKND(next)
BOOST_MPL_AUX_COMMON_NAME_WKND(prior)
template<
typename BOOST_MPL_AUX_NA_PARAM(T)// typename T = na
>
struct next
{
typedef typename T::next type;
BOOST_MPL_AUX_LAMBDA_SUPPORT(1,next,(T))
};
template<
typename BOOST_MPL_AUX_NA_PARAM(T)
>
struct prior
{
typedef typename T::prior type;
BOOST_MPL_AUX_LAMBDA_SUPPORT(1,prior,(T))
};
BOOST_MPL_AUX_NA_SPEC(1, next)
BOOST_MPL_AUX_NA_SPEC(1, prior)
}}
namespace boost { namespace mpl {
//# define BOOST_MPL_AUX_NTTP_DECL(T, x) T x /**/
template<
typename Vector
,long n_
>
struct v_iter
{
typedef aux::v_iter_tag tag; //标记
typedef random_access_iterator_tag category;//迭代器类型
typedef typename v_at::type type;//这是在vector中特化的版本。
typedef Vector vector_;
typedef mpl::long_ pos;
#if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
enum {
next_ = n_ + 1
, prior_ = n_ - 1
, pos_ = n_
};
typedef v_iter next; //实际上重新生成一个v_iter
typedef v_iter prior;
#endif
};
#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
template<
typename Vector
, BOOST_MPL_AUX_NTTP_DECL(long, n_)//long n_
>
struct next< v_iter >//这儿来看，显然不主模版。因为这儿只有一个参数v_iter,是一个特化版本。
{
typedef v_iter type;//重新生成一个v_iter
};
template<
typename Vector
, BOOST_MPL_AUX_NTTP_DECL(long, n_)
>
struct prior< v_iter >//同上面一样。
{
typedef v_iter type;//重新生成一个v_iter
};
# define BOOST_MPL_AUX_NESTED_VALUE_WKND(T, C) /
BOOST_MPL_AUX_VALUE_WKND(C)::value /
/**/
# define BOOST_MPL_AUX_VALUE_WKND(C) C
#endif
}}
#endif // BOOST_MPL_AUX_VECTOR_ITERATOR_HPP_INCLUDED
namespace boost { namespace mpl {
//特化版本，在其他地方声明
template< typename V >
struct v_at< V,0 >
{
typedef typename V::item0 type;//V代表的是vector,item0就是第一个元素值。
};
template<
typename T0
>
struct vector1
{ //这仅是一个标记，只对它进行了声明，没有对它进行定义。代表一个特定的类型。
typedef aux::vector_tag<1> tag;
typedef vector1 type;
typedef T0 item0;//vector1存放的元素T0
typedef void_ item1;//
typedef T0 back;
typedef v_iter< type,0 > begin; //
typedef v_iter< type,1 > end;
};
template<>
struct push_front_impl< aux::vector_tag<0> >
{
template< typename Vector, typename T > struct apply
{
typedef vector1 type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<1> >
{
template< typename Vector > struct apply
{
typedef vector0< //对于vector1来说，pop出一个元素之后，就没有任何元素了。
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<0> >
{
template< typename Vector, typename T > struct apply
{
typedef vector1< //同样重新生成一个vector1，模板元是不能改变其元素值。
//要改变只得重新生成一个新的vector。
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<1> >
{
template< typename Vector > struct apply
{
typedef vector0 type;
};
};
template< typename V >
struct v_at< V,1 >
{
typedef typename V::item1 type;//vector的第二个元素值，比较直接。
};
//下面的特化版本同上面的非常类似。而代码写得很清晰，而又直接。
template<
typename T0, typename T1
>
struct vector2
{
typedef aux::vector_tag<2> tag;
typedef vector2 type;
typedef T0 item0;
typedef T1 item1;
typedef void_ item2;
typedef T1 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,2 > end;
};
template<>
struct push_front_impl< aux::vector_tag<1> >
{
template< typename Vector, typename T > struct apply
{
typedef vector2<
T
,
typename Vector::item0
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<2> >
{
template< typename Vector > struct apply
{
typedef vector1<
typename Vector::item1
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<1> >
{
template< typename Vector, typename T > struct apply
{
typedef vector2<
typename Vector::item0
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<2> >
{
template< typename Vector > struct apply
{
typedef vector1<
typename Vector::item0
> type;
};
};
template< typename V >
struct v_at< V,2 >
{
typedef typename V::item2 type;
};
template<
typename T0, typename T1, typename T2
>
struct vector3
{
typedef aux::vector_tag<3> tag;
typedef vector3 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef void_ item3;
typedef T2 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,3 > end;
};
template<>
struct push_front_impl< aux::vector_tag<2> >
{
template< typename Vector, typename T > struct apply
{
typedef vector3<
T
,
typename Vector::item0, typename Vector::item1
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<3> >
{
template< typename Vector > struct apply
{
typedef vector2<
typename Vector::item1, typename Vector::item2
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<2> >
{
template< typename Vector, typename T > struct apply
{
typedef vector3<
typename Vector::item0, typename Vector::item1
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<3> >
{
template< typename Vector > struct apply
{
typedef vector2<
typename Vector::item0, typename Vector::item1
> type;
};
};
template< typename V >
struct v_at< V,3 >
{
typedef typename V::item3 type;
};
template<
typename T0, typename T1, typename T2, typename T3
>
struct vector4
{
typedef aux::vector_tag<4> tag;
typedef vector4 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef void_ item4;
typedef T3 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,4 > end;
};
template<>
struct push_front_impl< aux::vector_tag<3> >
{
template< typename Vector, typename T > struct apply
{
typedef vector4<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<4> >
{
template< typename Vector > struct apply
{
typedef vector3<
typename Vector::item1, typename Vector::item2
, typename Vector::item3
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<3> >
{
template< typename Vector, typename T > struct apply
{
typedef vector4<
typename Vector::item0, typename Vector::item1
, typename Vector::item2
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<4> >
{
template< typename Vector > struct apply
{
typedef vector3<
typename Vector::item0, typename Vector::item1
, typename Vector::item2
> type;
};
};
template< typename V >
struct v_at< V,4 >
{
typedef typename V::item4 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
>
struct vector5
{
typedef aux::vector_tag<5> tag;
typedef vector5 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef void_ item5;
typedef T4 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,5 > end;
};
template<>
struct push_front_impl< aux::vector_tag<4> >
{
template< typename Vector, typename T > struct apply
{
typedef vector5<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<5> >
{
template< typename Vector > struct apply
{
typedef vector4<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<4> >
{
template< typename Vector, typename T > struct apply
{
typedef vector5<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<5> >
{
template< typename Vector > struct apply
{
typedef vector4<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
> type;
};
};
template< typename V >
struct v_at< V,5 >
{
typedef typename V::item5 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
, typename T5
>
struct vector6
{
typedef aux::vector_tag<6> tag;
typedef vector6 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef T5 item5;
typedef void_ item6;
typedef T5 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,6 > end;
};
template<>
struct push_front_impl< aux::vector_tag<5> >
{
template< typename Vector, typename T > struct apply
{
typedef vector6<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<6> >
{
template< typename Vector > struct apply
{
typedef vector5<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
, typename Vector::item5
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<5> >
{
template< typename Vector, typename T > struct apply
{
typedef vector6<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<6> >
{
template< typename Vector > struct apply
{
typedef vector5<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4
> type;
};
};
template< typename V >
struct v_at< V,6 >
{
typedef typename V::item6 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
, typename T5, typename T6
>
struct vector7
{
typedef aux::vector_tag<7> tag;
typedef vector7 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef T5 item5;
typedef T6 item6;
typedef void_ item7;
typedef T6 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,7 > end;
};
template<>
struct push_front_impl< aux::vector_tag<6> >
{
template< typename Vector, typename T > struct apply
{
typedef vector7<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<7> >
{
template< typename Vector > struct apply
{
typedef vector6<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
, typename Vector::item5, typename Vector::item6
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<6> >
{
template< typename Vector, typename T > struct apply
{
typedef vector7<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<7> >
{
template< typename Vector > struct apply
{
typedef vector6<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
> type;
};
};
template< typename V >
struct v_at< V,7 >
{
typedef typename V::item7 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
, typename T5, typename T6, typename T7
>
struct vector8
{
typedef aux::vector_tag<8> tag;
typedef vector8 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef T5 item5;
typedef T6 item6;
typedef T7 item7;
typedef void_ item8;
typedef T7 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,8 > end;
};
template<>
struct push_front_impl< aux::vector_tag<7> >
{
template< typename Vector, typename T > struct apply
{
typedef vector8<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<8> >
{
template< typename Vector > struct apply
{
typedef vector7<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
, typename Vector::item5, typename Vector::item6
, typename Vector::item7
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<7> >
{
template< typename Vector, typename T > struct apply
{
typedef vector8<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<8> >
{
template< typename Vector > struct apply
{
typedef vector7<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6
> type;
};
};
template< typename V >
struct v_at< V,8 >
{
typedef typename V::item8 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
, typename T5, typename T6, typename T7, typename T8
>
struct vector9
{
typedef aux::vector_tag<9> tag;
typedef vector9 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef T5 item5;
typedef T6 item6;
typedef T7 item7;
typedef T8 item8;
typedef void_ item9;
typedef T8 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,9 > end;
};
template<>
struct push_front_impl< aux::vector_tag<8> >
{
template< typename Vector, typename T > struct apply
{
typedef vector9<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<9> >
{
template< typename Vector > struct apply
{
typedef vector8<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
, typename Vector::item5, typename Vector::item6
, typename Vector::item7, typename Vector::item8
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<8> >
{
template< typename Vector, typename T > struct apply
{
typedef vector9<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<9> >
{
template< typename Vector > struct apply
{
typedef vector8<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
> type;
};
};
template< typename V >
struct v_at< V,9 >
{
typedef typename V::item9 type;
};
template<
typename T0, typename T1, typename T2, typename T3, typename T4
, typename T5, typename T6, typename T7, typename T8, typename T9
>
struct vector10
{ //vector_tag只有声明，没有定义。在这儿表示类型,不需要定义，只是一个标记。
typedef aux::vector_tag<10> tag;
typedef vector10 type;
typedef T0 item0;
typedef T1 item1;
typedef T2 item2;
typedef T3 item3;
typedef T4 item4;
typedef T5 item5;
typedef T6 item6;
typedef T7 item7;
typedef T8 item8;
typedef T9 item9;
typedef void_ item10;
typedef T9 back;
typedef v_iter< type,0 > begin;
typedef v_iter< type,10 > end;
};
template<>
struct push_front_impl< aux::vector_tag<9> >
{
template< typename Vector, typename T > struct apply
{
typedef vector10<
T
,
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
, typename Vector::item8
> type;
};
};
template<>
struct pop_front_impl< aux::vector_tag<10> >
{
template< typename Vector > struct apply
{
typedef vector9<
typename Vector::item1, typename Vector::item2
, typename Vector::item3, typename Vector::item4
, typename Vector::item5, typename Vector::item6
, typename Vector::item7, typename Vector::item8
, typename Vector::item9
> type;
};
};
template<>
struct push_back_impl< aux::vector_tag<9> >
{
template< typename Vector, typename T > struct apply
{
typedef vector10<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
, typename Vector::item8
,
T
> type;
};
};
template<>
struct pop_back_impl< aux::vector_tag<10> >
{
template< typename Vector > struct apply
{
typedef vector9<
typename Vector::item0, typename Vector::item1
, typename Vector::item2, typename Vector::item3
, typename Vector::item4, typename Vector::item5
, typename Vector::item6, typename Vector::item7
, typename Vector::item8
> type;
};
};
template< typename V >
struct v_at< V,10 >
{
typedef typename V::item10 type;
};
}}
