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From: Tobias Schwinger (tschwinger_at_[hidden])
Date: 2004-10-17 08:50:00
JOAQUIN LOPEZ MU?Z wrote:
> ----- Mensaje original -----
> De: Tobias Schwinger <tschwinger_at_[hidden]>
> Fecha: Domingo, Octubre 17, 2004 1:01 pm
> Asunto: [boost] Re: [tuple] attempt to fix a BCB regression,and a plea
> for help
>
>
>>JOAQUIN LOPEZ MU?Z wrote:
>>
>>>Umm... This got me thinking, maybe the whole BCB-specific
>>>patch is just overkill, and it only takes to avoid
>>>the add_const<> construct.
>>>The attached file does just this, i.e. it relies on
>>>the default implementation for element<>, using
>>>plain const-qualifying instead of add_const<> for
>>>BCB. Would you be so kind to give it a try? Thanks in
>>>advance.
>>>
>>
>>This new version compiles fine with BCC 5.6.4 but does not compile
>>with
>>BCC 5.5.1 (and versions below this, according to Boost.Config).
>>
>>The patch is the difference from the file attached to the post I
>>reply
>>to (and not the first file you sent) and makes it work again.
>>
>>It uses the previous workaround in case
>>BOOST_NO_CV_SPECIALIZATIONS is set.
>>Another check for BCB within this block could be made in order to
>>use
>>'add_const' for compilers where it works fine (I omitted it, for now).
>>
>>
>>Here's my (still fuzzy) problem analysis:
>>
>>1. The "BCC <= 5.5.1 - problem" is that for these versions of BCC
>>cv-specializations don't work.
>>
>>2. The "add_const - problem" could have something todo with the
>>fact
>>that for BCC 'type const' and 'const type' can be different types.
>>[ see the note regarding the '__BORLANDC__' - block in
>>'is_const.hpp' ]
>
>
> As I understand it, the comment you refer to has to do
> with cv-qualifying references --not our problem now, I think.
>
>
>>I am not sure if and how this affects template argument
>>substitution,
>>but I changed
>>
>> typename T::head_type const
>>
>>to
>>
>> const typename T::head_type
>>
>>, just in case...
>>
>
>
> My only objection to your patch is that the problem
> with add_const is attributed to BOOST_BCB_PARTIAL_SPECIALIZATION_BUG
I think your objection is very right. I agree that it should be changed.
> Do you have any reason to think so?
I used it (even though the name says somethings different) as:
BOOST_PLAIN_OLD_BCC_WITH_A_LOT_OF_TEMPLATE_BUGS.
I did this because I am not too well informed regarding the
latest/upcoming version:
There was an announcement from Borland that there will be a new BCC,
based on the EDG frontend (fall 2003).
I havent't heard anything about it since then and could not find any
hint on their website either.
However it seems there is a version 0x600 around - and I don't know if
it is EDG based, but according to Boost.Config a lot of bugs have been
fixed.
???????????????????????????????????????????????????????????????????????
Can someone please tell me where I can find this mysterious C++BuilderX
preview [ mentioned in boost/config/compiler/borland.hpp ] ??
???????????????????????????????????????????????????????????????????????
Just downloaded Mobile Studio 1.5 which contains version 5.6.5...
Tested versions are now: 5.5.1, 5.6.4 and 5.6.5.
> I'd prefer to
> have that part guarded by a simple __BORLANDC__ workaround,
> given our current (lack of) knowledge about what's
> causing the problem.
I changed [ see attachment ]
#ifdef BOOST_BCB_PARTIAL_SPECIALIZATION_BUG
to
#if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
hoping that the problem is fixed with 0x600.
> If no one complains, I'll commit this stuff to the
> CVS tomorrow. Thanks everyboydy for your help.
Regards,
Tobias
// tuple_basic.hpp -----------------------------------------------------
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi_at_[hidden])
//
// 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)
// For more information, see http://www.boost.org
// Outside help:
// This and that, Gary Powell.
// Fixed return types for get_head/get_tail
// ( and other bugs ) per suggestion of Jens Maurer
// simplified element type accessors + bug fix (Jeremy Siek)
// Several changes/additions according to suggestions by Douglas Gregor,
// William Kempf, Vesa Karvonen, John Max Skaller, Ed Brey, Beman Dawes,
// David Abrahams.
// Revision history:
// 2002 05 01 Hugo Duncan: Fix for Borland after Jaakko's previous changes
// 2002 04 18 Jaakko: tuple element types can be void or plain function
// types, as long as no object is created.
// Tuple objects can no hold even noncopyable types
// such as arrays.
// 2001 10 22 John Maddock
// Fixes for Borland C++
// 2001 08 30 David Abrahams
// Added default constructor for cons<>.
// -----------------------------------------------------------------
#ifndef BOOST_TUPLE_BASIC_HPP
#define BOOST_TUPLE_BASIC_HPP
#include <utility> // needed for the assignment from pair to tuple
#include "boost/type_traits/cv_traits.hpp"
#include "boost/type_traits/function_traits.hpp"
#include "boost/detail/workaround.hpp" // needed for BOOST_WORKAROUND
namespace boost {
namespace tuples {
// -- null_type --------------------------------------------------------
struct null_type {};
// a helper function to provide a const null_type type temporary
namespace detail {
inline const null_type cnull() { return null_type(); }
// -- if construct ------------------------------------------------
// Proposed by Krzysztof Czarnecki and Ulrich Eisenecker
template <bool If, class Then, class Else> struct IF { typedef Then RET; };
template <class Then, class Else> struct IF<false, Then, Else> {
typedef Else RET;
};
} // end detail
// - cons forward declaration -----------------------------------------------
template <class HT, class TT> struct cons;
// - tuple forward declaration -----------------------------------------------
template <
class T0 = null_type, class T1 = null_type, class T2 = null_type,
class T3 = null_type, class T4 = null_type, class T5 = null_type,
class T6 = null_type, class T7 = null_type, class T8 = null_type,
class T9 = null_type>
class tuple;
// tuple_length forward declaration
template<class T> struct length;
namespace detail {
// -- generate error template, referencing to non-existing members of this
// template is used to produce compilation errors intentionally
template<class T>
class generate_error;
// - cons getters --------------------------------------------------------
// called: get_class<N>::get<RETURN_TYPE>(aTuple)
template< int N >
struct get_class {
template<class RET, class HT, class TT >
inline static RET get(const cons<HT, TT>& t)
{
#if BOOST_WORKAROUND(__IBMCPP__,==600)
// vacpp 6.0 is not very consistent regarding the member template keyword
// Here it generates an error when the template keyword is used.
return get_class<N-1>::get<RET>(t.tail);
#else
return get_class<N-1>::BOOST_NESTED_TEMPLATE get<RET>(t.tail);
#endif
}
template<class RET, class HT, class TT >
inline static RET get(cons<HT, TT>& t)
{
#if BOOST_WORKAROUND(__IBMCPP__,==600)
return get_class<N-1>::get<RET>(t.tail);
#else
return get_class<N-1>::BOOST_NESTED_TEMPLATE get<RET>(t.tail);
#endif
}
};
template<>
struct get_class<0> {
template<class RET, class HT, class TT>
inline static RET get(const cons<HT, TT>& t)
{
return t.head;
}
template<class RET, class HT, class TT>
inline static RET get(cons<HT, TT>& t)
{
return t.head;
}
};
} // end of namespace detail
// -cons type accessors ----------------------------------------
// typename tuples::element<N,T>::type gets the type of the
// Nth element ot T, first element is at index 0
// -------------------------------------------------------
#ifndef BOOST_NO_CV_SPECIALIZATIONS
template<int N, class T>
struct element
{
private:
typedef typename T::tail_type Next;
public:
typedef typename element<N-1, Next>::type type;
};
template<class T>
struct element<0,T>
{
typedef typename T::head_type type;
};
template<int N, class T>
struct element<N, const T>
{
private:
typedef typename T::tail_type Next;
typedef typename element<N-1, Next>::type unqualified_type;
public:
#if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
typedef const unqualified_type type;
#else
typedef typename boost::add_const<unqualified_type>::type type;
#endif
};
template<class T>
struct element<0,const T>
{
#if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
typedef const typename T::head_type type;
#else
typedef typename boost::add_const<typename T::head_type>::type type;
#endif
};
#else // def BOOST_NO_CV_SPECIALIZATIONS
namespace detail {
template<int N, class T, bool IsConst>
struct element_impl
{
private:
typedef typename T::tail_type Next;
public:
typedef typename element_impl<N-1, Next, IsConst>::type type;
};
template<int N, class T>
struct element_impl<N, T, true /* IsConst */>
{
private:
typedef typename T::tail_type Next;
public:
typedef const typename element_impl<N-1, Next, true>::type type;
};
template<class T>
struct element_impl<0, T, false /* IsConst */>
{
typedef typename T::head_type type;
};
template<class T>
struct element_impl<0, T, true /* IsConst */>
{
typedef const typename T::head_type type;
};
} // end of namespace detail
template<int N, class T>
struct element:
public detail::element_impl<N, T, ::boost::is_const<T>::value>
{
};
#endif
// -get function templates -----------------------------------------------
// Usage: get<N>(aTuple)
// -- some traits classes for get functions
// access traits lifted from detail namespace to be part of the interface,
// (Joel de Guzman's suggestion). Rationale: get functions are part of the
// interface, so should the way to express their return types be.
template <class T> struct access_traits {
typedef const T& const_type;
typedef T& non_const_type;
typedef const typename boost::remove_cv<T>::type& parameter_type;
// used as the tuple constructors parameter types
// Rationale: non-reference tuple element types can be cv-qualified.
// It should be possible to initialize such types with temporaries,
// and when binding temporaries to references, the reference must
// be non-volatile and const. 8.5.3. (5)
};
template <class T> struct access_traits<T&> {
typedef T& const_type;
typedef T& non_const_type;
typedef T& parameter_type;
};
// get function for non-const cons-lists, returns a reference to the element
template<int N, class HT, class TT>
inline typename access_traits<
typename element<N, cons<HT, TT> >::type
>::non_const_type
get(cons<HT, TT>& c BOOST_APPEND_EXPLICIT_TEMPLATE_NON_TYPE(int, N)) {
#if BOOST_WORKAROUND(__IBMCPP__,==600 )
return detail::get_class<N>::
#else
return detail::get_class<N>::BOOST_NESTED_TEMPLATE
#endif
get<
typename access_traits<
typename element<N, cons<HT, TT> >::type
>::non_const_type,
HT,TT
>(c);
}
// get function for const cons-lists, returns a const reference to
// the element. If the element is a reference, returns the reference
// as such (that is, can return a non-const reference)
template<int N, class HT, class TT>
inline typename access_traits<
typename element<N, cons<HT, TT> >::type
>::const_type
get(const cons<HT, TT>& c BOOST_APPEND_EXPLICIT_TEMPLATE_NON_TYPE(int, N)) {
#if BOOST_WORKAROUND(__IBMCPP__,==600)
return detail::get_class<N>::
#else
return detail::get_class<N>::BOOST_NESTED_TEMPLATE
#endif
get<
typename access_traits<
typename element<N, cons<HT, TT> >::type
>::const_type,
HT,TT
>(c);
}
// -- the cons template --------------------------------------------------
namespace detail {
// These helper templates wrap void types and plain function types.
// The reationale is to allow one to write tuple types with those types
// as elements, even though it is not possible to instantiate such object.
// E.g: typedef tuple<void> some_type; // ok
// but: some_type x; // fails
template <class T> class non_storeable_type {
non_storeable_type();
};
template <class T> struct wrap_non_storeable_type {
typedef typename IF<
::boost::is_function<T>::value, non_storeable_type<T>, T
>::RET type;
};
template <> struct wrap_non_storeable_type<void> {
typedef non_storeable_type<void> type;
};
} // detail
template <class HT, class TT>
struct cons {
typedef HT head_type;
typedef TT tail_type;
typedef typename
detail::wrap_non_storeable_type<head_type>::type stored_head_type;
stored_head_type head;
tail_type tail;
typename access_traits<stored_head_type>::non_const_type
get_head() { return head; }
typename access_traits<tail_type>::non_const_type
get_tail() { return tail; }
typename access_traits<stored_head_type>::const_type
get_head() const { return head; }
typename access_traits<tail_type>::const_type
get_tail() const { return tail; }
cons() : head(), tail() {}
// cons() : head(detail::default_arg<HT>::f()), tail() {}
// the argument for head is not strictly needed, but it prevents
// array type elements. This is good, since array type elements
// cannot be supported properly in any case (no assignment,
// copy works only if the tails are exactly the same type, ...)
cons(typename access_traits<stored_head_type>::parameter_type h,
const tail_type& t)
: head (h), tail(t) {}
template <class T1, class T2, class T3, class T4, class T5,
class T6, class T7, class T8, class T9, class T10>
cons( T1& t1, T2& t2, T3& t3, T4& t4, T5& t5,
T6& t6, T7& t7, T8& t8, T9& t9, T10& t10 )
: head (t1),
tail (t2, t3, t4, t5, t6, t7, t8, t9, t10, detail::cnull())
{}
template <class T2, class T3, class T4, class T5,
class T6, class T7, class T8, class T9, class T10>
cons( const null_type& t1, T2& t2, T3& t3, T4& t4, T5& t5,
T6& t6, T7& t7, T8& t8, T9& t9, T10& t10 )
: head (),
tail (t2, t3, t4, t5, t6, t7, t8, t9, t10, detail::cnull())
{}
template <class HT2, class TT2>
cons( const cons<HT2, TT2>& u ) : head(u.head), tail(u.tail) {}
template <class HT2, class TT2>
cons& operator=( const cons<HT2, TT2>& u ) {
head=u.head; tail=u.tail; return *this;
}
// must define assignment operator explicitly, implicit version is
// illformed if HT is a reference (12.8. (12))
cons& operator=(const cons& u) {
head = u.head; tail = u.tail; return *this;
}
template <class T1, class T2>
cons& operator=( const std::pair<T1, T2>& u ) {
BOOST_STATIC_ASSERT(length<cons>::value == 2); // check length = 2
head = u.first; tail.head = u.second; return *this;
}
// get member functions (non-const and const)
template <int N>
typename access_traits<
typename element<N, cons<HT, TT> >::type
>::non_const_type
get() {
return boost::tuples::get<N>(*this); // delegate to non-member get
}
template <int N>
typename access_traits<
typename element<N, cons<HT, TT> >::type
>::const_type
get() const {
return boost::tuples::get<N>(*this); // delegate to non-member get
}
};
template <class HT>
struct cons<HT, null_type> {
typedef HT head_type;
typedef null_type tail_type;
typedef cons<HT, null_type> self_type;
typedef typename
detail::wrap_non_storeable_type<head_type>::type stored_head_type;
stored_head_type head;
typename access_traits<stored_head_type>::non_const_type
get_head() { return head; }
null_type get_tail() { return null_type(); }
typename access_traits<stored_head_type>::const_type
get_head() const { return head; }
const null_type get_tail() const { return null_type(); }
// cons() : head(detail::default_arg<HT>::f()) {}
cons() : head() {}
cons(typename access_traits<stored_head_type>::parameter_type h,
const null_type& = null_type())
: head (h) {}
template<class T1>
cons(T1& t1, const null_type&, const null_type&, const null_type&,
const null_type&, const null_type&, const null_type&,
const null_type&, const null_type&, const null_type&)
: head (t1) {}
cons(const null_type&,
const null_type&, const null_type&, const null_type&,
const null_type&, const null_type&, const null_type&,
const null_type&, const null_type&, const null_type&)
: head () {}
template <class HT2>
cons( const cons<HT2, null_type>& u ) : head(u.head) {}
template <class HT2>
cons& operator=(const cons<HT2, null_type>& u )
{ head = u.head; return *this; }
// must define assignment operator explicitely, implicit version
// is illformed if HT is a reference
cons& operator=(const cons& u) { head = u.head; return *this; }
template <int N>
typename access_traits<
typename element<N, self_type>::type
>::non_const_type
get(BOOST_EXPLICIT_TEMPLATE_NON_TYPE(int, N)) {
return boost::tuples::get<N>(*this);
}
template <int N>
typename access_traits<
typename element<N, self_type>::type
>::const_type
get(BOOST_EXPLICIT_TEMPLATE_NON_TYPE(int, N)) const {
return boost::tuples::get<N>(*this);
}
};
// templates for finding out the length of the tuple -------------------
template<class T>
struct length {
BOOST_STATIC_CONSTANT(int, value = 1 + length<typename T::tail_type>::value);
};
template<>
struct length<tuple<> > {
BOOST_STATIC_CONSTANT(int, value = 0);
};
template<>
struct length<null_type> {
BOOST_STATIC_CONSTANT(int, value = 0);
};
namespace detail {
// Tuple to cons mapper --------------------------------------------------
template <class T0, class T1, class T2, class T3, class T4,
class T5, class T6, class T7, class T8, class T9>
struct map_tuple_to_cons
{
typedef cons<T0,
typename map_tuple_to_cons<T1, T2, T3, T4, T5,
T6, T7, T8, T9, null_type>::type
> type;
};
// The empty tuple is a null_type
template <>
struct map_tuple_to_cons<null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type>
{
typedef null_type type;
};
} // end detail
// -------------------------------------------------------------------
// -- tuple ------------------------------------------------------
template <class T0, class T1, class T2, class T3, class T4,
class T5, class T6, class T7, class T8, class T9>
class tuple :
public detail::map_tuple_to_cons<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::type
{
public:
typedef typename
detail::map_tuple_to_cons<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::type inherited;
typedef typename inherited::head_type head_type;
typedef typename inherited::tail_type tail_type;
// access_traits<T>::parameter_type takes non-reference types as const T&
tuple() {}
tuple(typename access_traits<T0>::parameter_type t0)
: inherited(t0, detail::cnull(), detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1)
: inherited(t0, t1, detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2)
: inherited(t0, t1, t2, detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3)
: inherited(t0, t1, t2, t3, detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull(),
detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4)
: inherited(t0, t1, t2, t3, t4, detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4,
typename access_traits<T5>::parameter_type t5)
: inherited(t0, t1, t2, t3, t4, t5, detail::cnull(), detail::cnull(),
detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4,
typename access_traits<T5>::parameter_type t5,
typename access_traits<T6>::parameter_type t6)
: inherited(t0, t1, t2, t3, t4, t5, t6, detail::cnull(),
detail::cnull(), detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4,
typename access_traits<T5>::parameter_type t5,
typename access_traits<T6>::parameter_type t6,
typename access_traits<T7>::parameter_type t7)
: inherited(t0, t1, t2, t3, t4, t5, t6, t7, detail::cnull(),
detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4,
typename access_traits<T5>::parameter_type t5,
typename access_traits<T6>::parameter_type t6,
typename access_traits<T7>::parameter_type t7,
typename access_traits<T8>::parameter_type t8)
: inherited(t0, t1, t2, t3, t4, t5, t6, t7, t8, detail::cnull()) {}
tuple(typename access_traits<T0>::parameter_type t0,
typename access_traits<T1>::parameter_type t1,
typename access_traits<T2>::parameter_type t2,
typename access_traits<T3>::parameter_type t3,
typename access_traits<T4>::parameter_type t4,
typename access_traits<T5>::parameter_type t5,
typename access_traits<T6>::parameter_type t6,
typename access_traits<T7>::parameter_type t7,
typename access_traits<T8>::parameter_type t8,
typename access_traits<T9>::parameter_type t9)
: inherited(t0, t1, t2, t3, t4, t5, t6, t7, t8, t9) {}
template<class U1, class U2>
tuple(const cons<U1, U2>& p) : inherited(p) {}
template <class U1, class U2>
tuple& operator=(const cons<U1, U2>& k) {
inherited::operator=(k);
return *this;
}
template <class U1, class U2>
tuple& operator=(const std::pair<U1, U2>& k) {
BOOST_STATIC_ASSERT(length<tuple>::value == 2);// check_length = 2
this->head = k.first;
this->tail.head = k.second;
return *this;
}
};
// The empty tuple
template <>
class tuple<null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type, null_type> :
public null_type
{
public:
typedef null_type inherited;
};
// Swallows any assignment (by Doug Gregor)
namespace detail {
struct swallow_assign {
template<typename T>
swallow_assign const& operator=(const T&) const {
return *this;
}
};
} // namespace detail
// "ignore" allows tuple positions to be ignored when using "tie".
detail::swallow_assign const ignore = detail::swallow_assign();
// ---------------------------------------------------------------------------
// The call_traits for make_tuple
// Honours the reference_wrapper class.
// Must be instantiated with plain or const plain types (not with references)
// from template<class T> foo(const T& t) : make_tuple_traits<const T>::type
// from template<class T> foo(T& t) : make_tuple_traits<T>::type
// Conversions:
// T -> T,
// references -> compile_time_error
// reference_wrapper<T> -> T&
// const reference_wrapper<T> -> T&
// array -> const ref array
template<class T>
struct make_tuple_traits {
typedef T type;
// commented away, see below (JJ)
// typedef typename IF<
// boost::is_function<T>::value,
// T&,
// T>::RET type;
};
// The is_function test was there originally for plain function types,
// which can't be stored as such (we must either store them as references or
// pointers). Such a type could be formed if make_tuple was called with a
// reference to a function.
// But this would mean that a const qualified function type was formed in
// the make_tuple function and hence make_tuple can't take a function
// reference as a parameter, and thus T can't be a function type.
// So is_function test was removed.
// (14.8.3. says that type deduction fails if a cv-qualified function type
// is created. (It only applies for the case of explicitly specifying template
// args, though?)) (JJ)
template<class T>
struct make_tuple_traits<T&> {
typedef typename
detail::generate_error<T&>::
do_not_use_with_reference_type error;
};
// Arrays can't be stored as plain types; convert them to references.
// All arrays are converted to const. This is because make_tuple takes its
// parameters as const T& and thus the knowledge of the potential
// non-constness of actual argument is lost.
template<class T, int n> struct make_tuple_traits <T[n]> {
typedef const T (&type)[n];
};
template<class T, int n>
struct make_tuple_traits<const T[n]> {
typedef const T (&type)[n];
};
template<class T, int n> struct make_tuple_traits<volatile T[n]> {
typedef const volatile T (&type)[n];
};
template<class T, int n>
struct make_tuple_traits<const volatile T[n]> {
typedef const volatile T (&type)[n];
};
template<class T>
struct make_tuple_traits<reference_wrapper<T> >{
typedef T& type;
};
template<class T>
struct make_tuple_traits<const reference_wrapper<T> >{
typedef T& type;
};
namespace detail {
// a helper traits to make the make_tuple functions shorter (Vesa Karvonen's
// suggestion)
template <
class T0 = null_type, class T1 = null_type, class T2 = null_type,
class T3 = null_type, class T4 = null_type, class T5 = null_type,
class T6 = null_type, class T7 = null_type, class T8 = null_type,
class T9 = null_type
>
struct make_tuple_mapper {
typedef
tuple<typename make_tuple_traits<T0>::type,
typename make_tuple_traits<T1>::type,
typename make_tuple_traits<T2>::type,
typename make_tuple_traits<T3>::type,
typename make_tuple_traits<T4>::type,
typename make_tuple_traits<T5>::type,
typename make_tuple_traits<T6>::type,
typename make_tuple_traits<T7>::type,
typename make_tuple_traits<T8>::type,
typename make_tuple_traits<T9>::type> type;
};
} // end detail
// -make_tuple function templates -----------------------------------
inline tuple<> make_tuple() {
return tuple<>();
}
template<class T0>
inline typename detail::make_tuple_mapper<T0>::type
make_tuple(const T0& t0) {
typedef typename detail::make_tuple_mapper<T0>::type t;
return t(t0);
}
template<class T0, class T1>
inline typename detail::make_tuple_mapper<T0, T1>::type
make_tuple(const T0& t0, const T1& t1) {
typedef typename detail::make_tuple_mapper<T0, T1>::type t;
return t(t0, t1);
}
template<class T0, class T1, class T2>
inline typename detail::make_tuple_mapper<T0, T1, T2>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2) {
typedef typename detail::make_tuple_mapper<T0, T1, T2>::type t;
return t(t0, t1, t2);
}
template<class T0, class T1, class T2, class T3>
inline typename detail::make_tuple_mapper<T0, T1, T2, T3>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3) {
typedef typename detail::make_tuple_mapper<T0, T1, T2, T3>::type t;
return t(t0, t1, t2, t3);
}
template<class T0, class T1, class T2, class T3, class T4>
inline typename detail::make_tuple_mapper<T0, T1, T2, T3, T4>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4) {
typedef typename detail::make_tuple_mapper<T0, T1, T2, T3, T4>::type t;
return t(t0, t1, t2, t3, t4);
}
template<class T0, class T1, class T2, class T3, class T4, class T5>
inline typename detail::make_tuple_mapper<T0, T1, T2, T3, T4, T5>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4, const T5& t5) {
typedef typename detail::make_tuple_mapper<T0, T1, T2, T3, T4, T5>::type t;
return t(t0, t1, t2, t3, t4, t5);
}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline typename detail::make_tuple_mapper<T0, T1, T2, T3, T4, T5, T6>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4, const T5& t5, const T6& t6) {
typedef typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6>::type t;
return t(t0, t1, t2, t3, t4, t5, t6);
}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6,
class T7>
inline typename detail::make_tuple_mapper<T0, T1, T2, T3, T4, T5, T6, T7>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4, const T5& t5, const T6& t6, const T7& t7) {
typedef typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6, T7>::type t;
return t(t0, t1, t2, t3, t4, t5, t6, t7);
}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6,
class T7, class T8>
inline typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6, T7, T8>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4, const T5& t5, const T6& t6, const T7& t7,
const T8& t8) {
typedef typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6, T7, T8>::type t;
return t(t0, t1, t2, t3, t4, t5, t6, t7, t8);
}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6,
class T7, class T8, class T9>
inline typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::type
make_tuple(const T0& t0, const T1& t1, const T2& t2, const T3& t3,
const T4& t4, const T5& t5, const T6& t6, const T7& t7,
const T8& t8, const T9& t9) {
typedef typename detail::make_tuple_mapper
<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>::type t;
return t(t0, t1, t2, t3, t4, t5, t6, t7, t8, t9);
}
// Tie function templates -------------------------------------------------
template<class T1>
inline tuple<T1&> tie(T1& t1) {
return tuple<T1&> (t1);
}
template<class T1, class T2>
inline tuple<T1&, T2&> tie(T1& t1, T2& t2) {
return tuple<T1&, T2&> (t1, t2);
}
template<class T1, class T2, class T3>
inline tuple<T1&, T2&, T3&> tie(T1& t1, T2& t2, T3& t3) {
return tuple<T1&, T2&, T3&> (t1, t2, t3);
}
template<class T1, class T2, class T3, class T4>
inline tuple<T1&, T2&, T3&, T4&> tie(T1& t1, T2& t2, T3& t3, T4& t4) {
return tuple<T1&, T2&, T3&, T4&> (t1, t2, t3, t4);
}
template<class T1, class T2, class T3, class T4, class T5>
inline tuple<T1&, T2&, T3&, T4&, T5&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5) {
return tuple<T1&, T2&, T3&, T4&, T5&> (t1, t2, t3, t4, t5);
}
template<class T1, class T2, class T3, class T4, class T5, class T6>
inline tuple<T1&, T2&, T3&, T4&, T5&, T6&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6) {
return tuple<T1&, T2&, T3&, T4&, T5&, T6&> (t1, t2, t3, t4, t5, t6);
}
template<class T1, class T2, class T3, class T4, class T5, class T6, class T7>
inline tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6, T7& t7) {
return tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&> (t1, t2, t3, t4, t5, t6, t7);
}
template<class T1, class T2, class T3, class T4, class T5, class T6, class T7,
class T8>
inline tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6, T7& t7, T8& t8) {
return tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&>
(t1, t2, t3, t4, t5, t6, t7, t8);
}
template<class T1, class T2, class T3, class T4, class T5, class T6, class T7,
class T8, class T9>
inline tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&, T9&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6, T7& t7, T8& t8,
T9& t9) {
return tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&, T9&>
(t1, t2, t3, t4, t5, t6, t7, t8, t9);
}
template<class T1, class T2, class T3, class T4, class T5, class T6, class T7,
class T8, class T9, class T10>
inline tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&, T9&, T10&>
tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6, T7& t7, T8& t8,
T9& t9, T10& t10) {
return tuple<T1&, T2&, T3&, T4&, T5&, T6&, T7&, T8&, T9&, T10&>
(t1, t2, t3, t4, t5, t6, t7, t8, t9, t10);
}
} // end of namespace tuples
} // end of namespace boost
#endif // BOOST_TUPLE_BASIC_HPP
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