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# ifndef MAPBOX_UTIL_VARIANT_HPP
# define MAPBOX_UTIL_VARIANT_HPP
# include <cassert>
# include <cstddef> // size_t
# include <new> // operator new
# include <stdexcept> // runtime_error
# include <string>
# include <tuple>
# include <type_traits>
# include <typeinfo>
# include <utility>
# include "recursive_wrapper.hpp"
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# include "variant_visitor.hpp"
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// clang-format off
// [[deprecated]] is only available in C++14, use this for the time being
# if __cplusplus <= 201103L
# ifdef __GNUC__
# define MAPBOX_VARIANT_DEPRECATED __attribute__((deprecated))
# elif defined(_MSC_VER)
# define MAPBOX_VARIANT_DEPRECATED __declspec(deprecated)
# else
# define MAPBOX_VARIANT_DEPRECATED
# endif
# else
# define MAPBOX_VARIANT_DEPRECATED [[deprecated]]
# endif
# ifdef _MSC_VER
// https://msdn.microsoft.com/en-us/library/bw1hbe6y.aspx
# ifdef NDEBUG
# define VARIANT_INLINE __forceinline
# else
# define VARIANT_INLINE //__declspec(noinline)
# endif
# else
# ifdef NDEBUG
# define VARIANT_INLINE //inline __attribute__((always_inline))
# else
# define VARIANT_INLINE __attribute__((noinline))
# endif
# endif
// clang-format on
// Exceptions
# if defined( __EXCEPTIONS) || defined( _MSC_VER)
# define HAS_EXCEPTIONS
# endif
# define VARIANT_MAJOR_VERSION 1
# define VARIANT_MINOR_VERSION 1
# define VARIANT_PATCH_VERSION 0
# define VARIANT_VERSION (VARIANT_MAJOR_VERSION * 100000) + (VARIANT_MINOR_VERSION * 100) + (VARIANT_PATCH_VERSION)
//namespace mapbox {
// namespace util {
namespace std {
// XXX This should derive from std::logic_error instead of std::runtime_error.
// See https://github.com/mapbox/variant/issues/48 for details.
class bad_variant_access : public std : : runtime_error
{
public :
explicit bad_variant_access ( const std : : string & what_arg )
: runtime_error ( what_arg ) { }
explicit bad_variant_access ( const char * what_arg )
: runtime_error ( what_arg ) { }
} ; // class bad_variant_access
namespace detail {
static constexpr std : : size_t invalid_value = std : : size_t ( - 1 ) ;
template < typename T , typename . . . Types >
struct direct_type ;
template < typename T , typename First , typename . . . Types >
struct direct_type < T , First , Types . . . >
{
static constexpr std : : size_t index = std : : is_same < T , First > : : value
? sizeof . . . ( Types )
: direct_type < T , Types . . . > : : index ;
} ;
template < typename T >
struct direct_type < T >
{
static constexpr std : : size_t index = invalid_value ;
} ;
# if __cpp_lib_logical_traits >= 201510L
using std : : disjunction ;
# else
template < typename . . . >
struct disjunction : std : : false_type { } ;
template < typename B1 >
struct disjunction < B1 > : B1 { } ;
template < typename B1 , typename B2 >
struct disjunction < B1 , B2 > : std : : conditional < B1 : : value , B1 , B2 > : : type { } ;
template < typename B1 , typename . . . Bs >
struct disjunction < B1 , Bs . . . > : std : : conditional < B1 : : value , B1 , disjunction < Bs . . . > > : : type { } ;
# endif
template < typename T , typename . . . Types >
struct convertible_type ;
template < typename T , typename First , typename . . . Types >
struct convertible_type < T , First , Types . . . >
{
static constexpr std : : size_t index = std : : is_convertible < T , First > : : value
? disjunction < std : : is_convertible < T , Types > . . . > : : value ? invalid_value : sizeof . . . ( Types )
: convertible_type < T , Types . . . > : : index ;
} ;
template < typename T >
struct convertible_type < T >
{
static constexpr std : : size_t index = invalid_value ;
} ;
template < typename T , typename . . . Types >
struct value_traits
{
using value_type = typename std : : remove_const < typename std : : remove_reference < T > : : type > : : type ;
static constexpr std : : size_t direct_index = direct_type < value_type , Types . . . > : : index ;
static constexpr bool is_direct = direct_index ! = invalid_value ;
static constexpr std : : size_t index = is_direct ? direct_index : convertible_type < value_type , Types . . . > : : index ;
static constexpr bool is_valid = index ! = invalid_value ;
static constexpr std : : size_t tindex = is_valid ? sizeof . . . ( Types ) - index : 0 ;
using target_type = typename std : : tuple_element < tindex , std : : tuple < void , Types . . . > > : : type ;
} ;
template < typename T , typename R = void >
struct enable_if_type
{
using type = R ;
} ;
template < typename F , typename V , typename Enable = void >
struct result_of_unary_visit
{
using type = typename std : : result_of < F ( V & ) > : : type ;
} ;
template < typename F , typename V >
struct result_of_unary_visit < F , V , typename enable_if_type < typename F : : result_type > : : type >
{
using type = typename F : : result_type ;
} ;
template < typename F , typename V , typename Enable = void >
struct result_of_binary_visit
{
using type = typename std : : result_of < F ( V & , V & ) > : : type ;
} ;
template < typename F , typename V >
struct result_of_binary_visit < F , V , typename enable_if_type < typename F : : result_type > : : type >
{
using type = typename F : : result_type ;
} ;
template < std : : size_t arg1 , std : : size_t . . . others >
struct static_max ;
template < std : : size_t arg >
struct static_max < arg >
{
static const std : : size_t value = arg ;
} ;
template < std : : size_t arg1 , std : : size_t arg2 , std : : size_t . . . others >
struct static_max < arg1 , arg2 , others . . . >
{
static const std : : size_t value = arg1 > = arg2 ? static_max < arg1 , others . . . > : : value : static_max < arg2 , others . . . > : : value ;
} ;
template < typename . . . Types >
struct variant_helper ;
template < typename T , typename . . . Types >
struct variant_helper < T , Types . . . >
{
VARIANT_INLINE static void destroy ( const std : : size_t type_index , void * data )
{
if ( type_index = = sizeof . . . ( Types ) )
{
reinterpret_cast < T * > ( data ) - > ~ T ( ) ;
}
else
{
variant_helper < Types . . . > : : destroy ( type_index , data ) ;
}
}
VARIANT_INLINE static void move ( const std : : size_t old_type_index , void * old_value , void * new_value )
{
if ( old_type_index = = sizeof . . . ( Types ) )
{
new ( new_value ) T ( std : : move ( * reinterpret_cast < T * > ( old_value ) ) ) ;
}
else
{
variant_helper < Types . . . > : : move ( old_type_index , old_value , new_value ) ;
}
}
VARIANT_INLINE static void copy ( const std : : size_t old_type_index , const void * old_value , void * new_value )
{
if ( old_type_index = = sizeof . . . ( Types ) )
{
new ( new_value ) T ( * reinterpret_cast < const T * > ( old_value ) ) ;
}
else
{
variant_helper < Types . . . > : : copy ( old_type_index , old_value , new_value ) ;
}
}
} ;
template < >
struct variant_helper < >
{
VARIANT_INLINE static void destroy ( const std : : size_t , void * ) { }
VARIANT_INLINE static void move ( const std : : size_t , void * , void * ) { }
VARIANT_INLINE static void copy ( const std : : size_t , const void * , void * ) { }
} ;
template < typename T >
struct unwrapper
{
static T const & apply_const ( T const & obj ) { return obj ; }
static T & apply ( T & obj ) { return obj ; }
} ;
template < typename T >
struct unwrapper < recursive_wrapper < T > >
{
static auto apply_const ( recursive_wrapper < T > const & obj )
- > typename recursive_wrapper < T > : : type const &
{
return obj . get ( ) ;
}
static auto apply ( recursive_wrapper < T > & obj )
- > typename recursive_wrapper < T > : : type &
{
return obj . get ( ) ;
}
} ;
template < typename T >
struct unwrapper < std : : reference_wrapper < T > >
{
static auto apply_const ( std : : reference_wrapper < T > const & obj )
- > typename std : : reference_wrapper < T > : : type const &
{
return obj . get ( ) ;
}
static auto apply ( std : : reference_wrapper < T > & obj )
- > typename std : : reference_wrapper < T > : : type &
{
return obj . get ( ) ;
}
} ;
template < typename F , typename V , typename R , typename . . . Types >
struct dispatcher ;
template < typename F , typename V , typename R , typename T , typename . . . Types >
struct dispatcher < F , V , R , T , Types . . . >
{
VARIANT_INLINE static R apply_const ( V const & v , F & & f )
{
if ( v . template is < T > ( ) )
{
return f ( unwrapper < T > : : apply_const ( v . template get_unchecked < T > ( ) ) ) ;
}
else
{
return dispatcher < F , V , R , Types . . . > : : apply_const ( v , std : : forward < F > ( f ) ) ;
}
}
VARIANT_INLINE static R apply ( V & v , F & & f )
{
if ( v . template is < T > ( ) )
{
return f ( unwrapper < T > : : apply ( v . template get_unchecked < T > ( ) ) ) ;
}
else
{
return dispatcher < F , V , R , Types . . . > : : apply ( v , std : : forward < F > ( f ) ) ;
}
}
} ;
template < typename F , typename V , typename R , typename T >
struct dispatcher < F , V , R , T >
{
VARIANT_INLINE static R apply_const ( V const & v , F & & f )
{
return f ( unwrapper < T > : : apply_const ( v . template get_unchecked < T > ( ) ) ) ;
}
VARIANT_INLINE static R apply ( V & v , F & & f )
{
return f ( unwrapper < T > : : apply ( v . template get_unchecked < T > ( ) ) ) ;
}
} ;
template < typename F , typename V , typename R , typename T , typename . . . Types >
struct binary_dispatcher_rhs ;
template < typename F , typename V , typename R , typename T0 , typename T1 , typename . . . Types >
struct binary_dispatcher_rhs < F , V , R , T0 , T1 , Types . . . >
{
VARIANT_INLINE static R apply_const ( V const & lhs , V const & rhs , F & & f )
{
if ( rhs . template is < T1 > ( ) ) // call binary functor
{
return f ( unwrapper < T0 > : : apply_const ( lhs . template get_unchecked < T0 > ( ) ) ,
unwrapper < T1 > : : apply_const ( rhs . template get_unchecked < T1 > ( ) ) ) ;
}
else
{
return binary_dispatcher_rhs < F , V , R , T0 , Types . . . > : : apply_const ( lhs , rhs , std : : forward < F > ( f ) ) ;
}
}
VARIANT_INLINE static R apply ( V & lhs , V & rhs , F & & f )
{
if ( rhs . template is < T1 > ( ) ) // call binary functor
{
return f ( unwrapper < T0 > : : apply ( lhs . template get_unchecked < T0 > ( ) ) ,
unwrapper < T1 > : : apply ( rhs . template get_unchecked < T1 > ( ) ) ) ;
}
else
{
return binary_dispatcher_rhs < F , V , R , T0 , Types . . . > : : apply ( lhs , rhs , std : : forward < F > ( f ) ) ;
}
}
} ;
template < typename F , typename V , typename R , typename T0 , typename T1 >
struct binary_dispatcher_rhs < F , V , R , T0 , T1 >
{
VARIANT_INLINE static R apply_const ( V const & lhs , V const & rhs , F & & f )
{
return f ( unwrapper < T0 > : : apply_const ( lhs . template get_unchecked < T0 > ( ) ) ,
unwrapper < T1 > : : apply_const ( rhs . template get_unchecked < T1 > ( ) ) ) ;
}
VARIANT_INLINE static R apply ( V & lhs , V & rhs , F & & f )
{
return f ( unwrapper < T0 > : : apply ( lhs . template get_unchecked < T0 > ( ) ) ,
unwrapper < T1 > : : apply ( rhs . template get_unchecked < T1 > ( ) ) ) ;
}
} ;
template < typename F , typename V , typename R , typename T , typename . . . Types >
struct binary_dispatcher_lhs ;
template < typename F , typename V , typename R , typename T0 , typename T1 , typename . . . Types >
struct binary_dispatcher_lhs < F , V , R , T0 , T1 , Types . . . >
{
VARIANT_INLINE static R apply_const ( V const & lhs , V const & rhs , F & & f )
{
if ( lhs . template is < T1 > ( ) ) // call binary functor
{
return f ( unwrapper < T1 > : : apply_const ( lhs . template get_unchecked < T1 > ( ) ) ,
unwrapper < T0 > : : apply_const ( rhs . template get_unchecked < T0 > ( ) ) ) ;
}
else
{
return binary_dispatcher_lhs < F , V , R , T0 , Types . . . > : : apply_const ( lhs , rhs , std : : forward < F > ( f ) ) ;
}
}
VARIANT_INLINE static R apply ( V & lhs , V & rhs , F & & f )
{
if ( lhs . template is < T1 > ( ) ) // call binary functor
{
return f ( unwrapper < T1 > : : apply ( lhs . template get_unchecked < T1 > ( ) ) ,
unwrapper < T0 > : : apply ( rhs . template get_unchecked < T0 > ( ) ) ) ;
}
else
{
return binary_dispatcher_lhs < F , V , R , T0 , Types . . . > : : apply ( lhs , rhs , std : : forward < F > ( f ) ) ;
}
}
} ;
template < typename F , typename V , typename R , typename T0 , typename T1 >
struct binary_dispatcher_lhs < F , V , R , T0 , T1 >
{
VARIANT_INLINE static R apply_const ( V const & lhs , V const & rhs , F & & f )
{
return f ( unwrapper < T1 > : : apply_const ( lhs . template get_unchecked < T1 > ( ) ) ,
unwrapper < T0 > : : apply_const ( rhs . template get_unchecked < T0 > ( ) ) ) ;
}
VARIANT_INLINE static R apply ( V & lhs , V & rhs , F & & f )
{
return f ( unwrapper < T1 > : : apply ( lhs . template get_unchecked < T1 > ( ) ) ,
unwrapper < T0 > : : apply ( rhs . template get_unchecked < T0 > ( ) ) ) ;
}
} ;
template < typename F , typename V , typename R , typename . . . Types >
struct binary_dispatcher ;
template < typename F , typename V , typename R , typename T , typename . . . Types >
struct binary_dispatcher < F , V , R , T , Types . . . >
{
VARIANT_INLINE static R apply_const ( V const & v0 , V const & v1 , F & & f )
{
if ( v0 . template is < T > ( ) )
{
if ( v1 . template is < T > ( ) )
{
return f ( unwrapper < T > : : apply_const ( v0 . template get_unchecked < T > ( ) ) ,
unwrapper < T > : : apply_const ( v1 . template get_unchecked < T > ( ) ) ) ; // call binary functor
}
else
{
return binary_dispatcher_rhs < F , V , R , T , Types . . . > : : apply_const ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
}
else if ( v1 . template is < T > ( ) )
{
return binary_dispatcher_lhs < F , V , R , T , Types . . . > : : apply_const ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
return binary_dispatcher < F , V , R , Types . . . > : : apply_const ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
VARIANT_INLINE static R apply ( V & v0 , V & v1 , F & & f )
{
if ( v0 . template is < T > ( ) )
{
if ( v1 . template is < T > ( ) )
{
return f ( unwrapper < T > : : apply ( v0 . template get_unchecked < T > ( ) ) ,
unwrapper < T > : : apply ( v1 . template get_unchecked < T > ( ) ) ) ; // call binary functor
}
else
{
return binary_dispatcher_rhs < F , V , R , T , Types . . . > : : apply ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
}
else if ( v1 . template is < T > ( ) )
{
return binary_dispatcher_lhs < F , V , R , T , Types . . . > : : apply ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
return binary_dispatcher < F , V , R , Types . . . > : : apply ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
} ;
template < typename F , typename V , typename R , typename T >
struct binary_dispatcher < F , V , R , T >
{
VARIANT_INLINE static R apply_const ( V const & v0 , V const & v1 , F & & f )
{
return f ( unwrapper < T > : : apply_const ( v0 . template get_unchecked < T > ( ) ) ,
unwrapper < T > : : apply_const ( v1 . template get_unchecked < T > ( ) ) ) ; // call binary functor
}
VARIANT_INLINE static R apply ( V & v0 , V & v1 , F & & f )
{
return f ( unwrapper < T > : : apply ( v0 . template get_unchecked < T > ( ) ) ,
unwrapper < T > : : apply ( v1 . template get_unchecked < T > ( ) ) ) ; // call binary functor
}
} ;
// comparator functors
struct equal_comp
{
template < typename T >
bool operator ( ) ( T const & lhs , T const & rhs ) const
{
return lhs = = rhs ;
}
} ;
struct less_comp
{
template < typename T >
bool operator ( ) ( T const & lhs , T const & rhs ) const
{
return lhs < rhs ;
}
} ;
template < typename Variant , typename Comp >
class comparer
{
public :
explicit comparer ( Variant const & lhs ) noexcept
: lhs_ ( lhs ) { }
comparer & operator = ( comparer const & ) = delete ;
// visitor
template < typename T >
bool operator ( ) ( T const & rhs_content ) const
{
T const & lhs_content = lhs_ . template get_unchecked < T > ( ) ;
return Comp ( ) ( lhs_content , rhs_content ) ;
}
private :
Variant const & lhs_ ;
} ;
} // namespace detail
struct no_init
{
} ;
template < typename . . . Types >
class variant
{
static_assert ( sizeof . . . ( Types ) > 0 , " Template parameter type list of variant can not be empty " ) ;
static_assert ( ! detail : : disjunction < std : : is_reference < Types > . . . > : : value , " Variant can not hold reference types. Maybe use std::reference_wrapper? " ) ;
private :
static const std : : size_t data_size = detail : : static_max < sizeof ( Types ) . . . > : : value ;
static const std : : size_t data_align = detail : : static_max < alignof ( Types ) . . . > : : value ;
using first_type = typename std : : tuple_element < 0 , std : : tuple < Types . . . > > : : type ;
using data_type = typename std : : aligned_storage < data_size , data_align > : : type ;
using helper_type = detail : : variant_helper < Types . . . > ;
std : : size_t type_index ;
data_type data ;
public :
VARIANT_INLINE variant ( ) noexcept ( std : : is_nothrow_default_constructible < first_type > : : value )
: type_index ( sizeof . . . ( Types ) - 1 )
{
static_assert ( std : : is_default_constructible < first_type > : : value , " First type in variant must be default constructible to allow default construction of variant " ) ;
new ( & data ) first_type ( ) ;
}
VARIANT_INLINE variant ( no_init ) noexcept
: type_index ( detail : : invalid_value ) { }
// http://isocpp.org/blog/2012/11/universal-references-in-c11-scott-meyers
template < typename T , typename Traits = detail : : value_traits < T , Types . . . > ,
typename Enable = typename std : : enable_if < Traits : : is_valid > : : type >
VARIANT_INLINE variant ( T & & val ) noexcept ( std : : is_nothrow_constructible < typename Traits : : target_type , T & & > : : value )
: type_index ( Traits : : index )
{
new ( & data ) typename Traits : : target_type ( std : : forward < T > ( val ) ) ;
}
VARIANT_INLINE variant ( variant < Types . . . > const & old )
: type_index ( old . type_index )
{
helper_type : : copy ( old . type_index , & old . data , & data ) ;
}
VARIANT_INLINE variant ( variant < Types . . . > & & old ) noexcept ( std : : is_nothrow_move_constructible < std : : tuple < Types . . . > > : : value )
: type_index ( old . type_index )
{
helper_type : : move ( old . type_index , & old . data , & data ) ;
}
private :
VARIANT_INLINE void copy_assign ( variant < Types . . . > const & rhs )
{
helper_type : : destroy ( type_index , & data ) ;
type_index = detail : : invalid_value ;
helper_type : : copy ( rhs . type_index , & rhs . data , & data ) ;
type_index = rhs . type_index ;
}
VARIANT_INLINE void move_assign ( variant < Types . . . > & & rhs )
{
helper_type : : destroy ( type_index , & data ) ;
type_index = detail : : invalid_value ;
helper_type : : move ( rhs . type_index , & rhs . data , & data ) ;
type_index = rhs . type_index ;
}
public :
VARIANT_INLINE variant < Types . . . > & operator = ( variant < Types . . . > & & other )
{
move_assign ( std : : move ( other ) ) ;
return * this ;
}
VARIANT_INLINE variant < Types . . . > & operator = ( variant < Types . . . > const & other )
{
copy_assign ( other ) ;
return * this ;
}
// conversions
// move-assign
template < typename T >
VARIANT_INLINE variant < Types . . . > & operator = ( T & & rhs ) noexcept
{
variant < Types . . . > temp ( std : : forward < T > ( rhs ) ) ;
move_assign ( std : : move ( temp ) ) ;
return * this ;
}
// copy-assign
template < typename T >
VARIANT_INLINE variant < Types . . . > & operator = ( T const & rhs )
{
variant < Types . . . > temp ( rhs ) ;
copy_assign ( temp ) ;
return * this ;
}
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE bool is ( ) const
{
return type_index = = detail : : direct_type < T , Types . . . > : : index ;
}
template < typename T , typename std : : enable_if <
( detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE bool is ( ) const
{
return type_index = = detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ;
}
VARIANT_INLINE bool valid ( ) const
{
return type_index ! = detail : : invalid_value ;
}
template < typename T , typename . . . Args >
VARIANT_INLINE void set ( Args & & . . . args )
{
helper_type : : destroy ( type_index , & data ) ;
type_index = detail : : invalid_value ;
new ( & data ) T ( std : : forward < Args > ( args ) . . . ) ;
type_index = detail : : direct_type < T , Types . . . > : : index ;
}
// get_unchecked<T>()
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get_unchecked ( )
{
return * reinterpret_cast < T * > ( & data ) ;
}
# ifdef HAS_EXCEPTIONS
// get<T>()
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get ( )
{
if ( type_index = = detail : : direct_type < T , Types . . . > : : index )
{
return * reinterpret_cast < T * > ( & data ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get_unchecked ( ) const
{
return * reinterpret_cast < T const * > ( & data ) ;
}
# ifdef HAS_EXCEPTIONS
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get ( ) const
{
if ( type_index = = detail : : direct_type < T , Types . . . > : : index )
{
return * reinterpret_cast < T const * > ( & data ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
// get_unchecked<T>() - T stored as recursive_wrapper<T>
template < typename T , typename std : : enable_if <
( detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get_unchecked ( )
{
return ( * reinterpret_cast < recursive_wrapper < T > * > ( & data ) ) . get ( ) ;
}
# ifdef HAS_EXCEPTIONS
// get<T>() - T stored as recursive_wrapper<T>
template < typename T , typename std : : enable_if <
( detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get ( )
{
if ( type_index = = detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index )
{
return ( * reinterpret_cast < recursive_wrapper < T > * > ( & data ) ) . get ( ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
template < typename T , typename std : : enable_if <
( detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get_unchecked ( ) const
{
return ( * reinterpret_cast < recursive_wrapper < T > const * > ( & data ) ) . get ( ) ;
}
# ifdef HAS_EXCEPTIONS
template < typename T , typename std : : enable_if <
( detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get ( ) const
{
if ( type_index = = detail : : direct_type < recursive_wrapper < T > , Types . . . > : : index )
{
return ( * reinterpret_cast < recursive_wrapper < T > const * > ( & data ) ) . get ( ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
// get_unchecked<T>() - T stored as std::reference_wrapper<T>
template < typename T , typename std : : enable_if <
( detail : : direct_type < std : : reference_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get_unchecked ( )
{
return ( * reinterpret_cast < std : : reference_wrapper < T > * > ( & data ) ) . get ( ) ;
}
# ifdef HAS_EXCEPTIONS
// get<T>() - T stored as std::reference_wrapper<T>
template < typename T , typename std : : enable_if <
( detail : : direct_type < std : : reference_wrapper < T > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T & get ( )
{
if ( type_index = = detail : : direct_type < std : : reference_wrapper < T > , Types . . . > : : index )
{
return ( * reinterpret_cast < std : : reference_wrapper < T > * > ( & data ) ) . get ( ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
template < typename T , typename std : : enable_if <
( detail : : direct_type < std : : reference_wrapper < T const > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get_unchecked ( ) const
{
return ( * reinterpret_cast < std : : reference_wrapper < T const > const * > ( & data ) ) . get ( ) ;
}
# ifdef HAS_EXCEPTIONS
template < typename T , typename std : : enable_if <
( detail : : direct_type < std : : reference_wrapper < T const > , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE T const & get ( ) const
{
if ( type_index = = detail : : direct_type < std : : reference_wrapper < T const > , Types . . . > : : index )
{
return ( * reinterpret_cast < std : : reference_wrapper < T const > const * > ( & data ) ) . get ( ) ;
}
else
{
throw bad_variant_access ( " in get<T>() " ) ;
}
}
# endif
// This function is deprecated because it returns an internal index field.
// Use which() instead.
MAPBOX_VARIANT_DEPRECATED VARIANT_INLINE std : : size_t get_type_index ( ) const
{
return type_index ;
}
VARIANT_INLINE int which ( ) const noexcept
{
return static_cast < int > ( sizeof . . . ( Types ) - type_index - 1 ) ;
}
template < typename T , typename std : : enable_if <
( detail : : direct_type < T , Types . . . > : : index ! = detail : : invalid_value ) > : : type * = nullptr >
VARIANT_INLINE static constexpr int which ( ) noexcept
{
return static_cast < int > ( sizeof . . . ( Types ) - detail : : direct_type < T , Types . . . > : : index - 1 ) ;
}
// visitor
// unary
template < typename F , typename V , typename R = typename detail : : result_of_unary_visit < F , first_type > : : type >
auto VARIANT_INLINE static visit ( V const & v , F & & f )
- > decltype ( detail : : dispatcher < F , V , R , Types . . . > : : apply_const ( v , std : : forward < F > ( f ) ) )
{
return detail : : dispatcher < F , V , R , Types . . . > : : apply_const ( v , std : : forward < F > ( f ) ) ;
}
// non-const
template < typename F , typename V , typename R = typename detail : : result_of_unary_visit < F , first_type > : : type >
auto VARIANT_INLINE static visit ( V & v , F & & f )
- > decltype ( detail : : dispatcher < F , V , R , Types . . . > : : apply ( v , std : : forward < F > ( f ) ) )
{
return detail : : dispatcher < F , V , R , Types . . . > : : apply ( v , std : : forward < F > ( f ) ) ;
}
// binary
// const
template < typename F , typename V , typename R = typename detail : : result_of_binary_visit < F , first_type > : : type >
auto VARIANT_INLINE static binary_visit ( V const & v0 , V const & v1 , F & & f )
- > decltype ( detail : : binary_dispatcher < F , V , R , Types . . . > : : apply_const ( v0 , v1 , std : : forward < F > ( f ) ) )
{
return detail : : binary_dispatcher < F , V , R , Types . . . > : : apply_const ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
// non-const
template < typename F , typename V , typename R = typename detail : : result_of_binary_visit < F , first_type > : : type >
auto VARIANT_INLINE static binary_visit ( V & v0 , V & v1 , F & & f )
- > decltype ( detail : : binary_dispatcher < F , V , R , Types . . . > : : apply ( v0 , v1 , std : : forward < F > ( f ) ) )
{
return detail : : binary_dispatcher < F , V , R , Types . . . > : : apply ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
2017-12-31 15:33:43 +00:00
// match
// unary
template < typename . . . Fs >
auto VARIANT_INLINE match ( Fs & & . . . fs ) const
- > decltype ( variant : : visit ( * this , : : std : : make_visitor ( std : : forward < Fs > ( fs ) . . . ) ) )
{
return variant : : visit ( * this , : : std : : make_visitor ( std : : forward < Fs > ( fs ) . . . ) ) ;
}
// non-const
template < typename . . . Fs >
auto VARIANT_INLINE match ( Fs & & . . . fs )
- > decltype ( variant : : visit ( * this , : : std : : make_visitor ( std : : forward < Fs > ( fs ) . . . ) ) )
{
return variant : : visit ( * this , : : std : : make_visitor ( std : : forward < Fs > ( fs ) . . . ) ) ;
}
2016-08-20 14:59:15 +00:00
~ variant ( ) noexcept // no-throw destructor
{
helper_type : : destroy ( type_index , & data ) ;
}
// comparison operators
// equality
VARIANT_INLINE bool operator = = ( variant const & rhs ) const
{
assert ( valid ( ) & & rhs . valid ( ) ) ;
if ( this - > which ( ) ! = rhs . which ( ) )
{
return false ;
}
detail : : comparer < variant , detail : : equal_comp > visitor ( * this ) ;
return visit ( rhs , visitor ) ;
}
VARIANT_INLINE bool operator ! = ( variant const & rhs ) const
{
return ! ( * this = = rhs ) ;
}
// less than
VARIANT_INLINE bool operator < ( variant const & rhs ) const
{
assert ( valid ( ) & & rhs . valid ( ) ) ;
if ( this - > which ( ) ! = rhs . which ( ) )
{
return this - > which ( ) < rhs . which ( ) ;
}
detail : : comparer < variant , detail : : less_comp > visitor ( * this ) ;
return visit ( rhs , visitor ) ;
}
VARIANT_INLINE bool operator > ( variant const & rhs ) const
{
return rhs < * this ;
}
VARIANT_INLINE bool operator < = ( variant const & rhs ) const
{
return ! ( * this > rhs ) ;
}
VARIANT_INLINE bool operator > = ( variant const & rhs ) const
{
return ! ( * this < rhs ) ;
}
} ;
// unary visitor interface
// const
template < typename F , typename V >
auto VARIANT_INLINE apply_visitor ( F & & f , V const & v ) - > decltype ( V : : visit ( v , std : : forward < F > ( f ) ) )
{
return V : : visit ( v , std : : forward < F > ( f ) ) ;
}
// non-const
template < typename F , typename V >
auto VARIANT_INLINE apply_visitor ( F & & f , V & v ) - > decltype ( V : : visit ( v , std : : forward < F > ( f ) ) )
{
return V : : visit ( v , std : : forward < F > ( f ) ) ;
}
// binary visitor interface
// const
template < typename F , typename V >
auto VARIANT_INLINE apply_visitor ( F & & f , V const & v0 , V const & v1 ) - > decltype ( V : : binary_visit ( v0 , v1 , std : : forward < F > ( f ) ) )
{
return V : : binary_visit ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
// non-const
template < typename F , typename V >
auto VARIANT_INLINE apply_visitor ( F & & f , V & v0 , V & v1 ) - > decltype ( V : : binary_visit ( v0 , v1 , std : : forward < F > ( f ) ) )
{
return V : : binary_visit ( v0 , v1 , std : : forward < F > ( f ) ) ;
}
// getter interface
# ifdef HAS_EXCEPTIONS
template < typename ResultType , typename T >
auto get ( T & var ) - > decltype ( var . template get < ResultType > ( ) )
{
return var . template get < ResultType > ( ) ;
}
# endif
template < typename ResultType , typename T >
ResultType & get_unchecked ( T & var )
{
return var . template get_unchecked < ResultType > ( ) ;
}
# ifdef HAS_EXCEPTIONS
template < typename ResultType , typename T >
auto get ( T const & var ) - > decltype ( var . template get < ResultType > ( ) )
{
return var . template get < ResultType > ( ) ;
}
# endif
template < typename ResultType , typename T >
ResultType const & get_unchecked ( T const & var )
{
return var . template get_unchecked < ResultType > ( ) ;
}
}
// } // namespace util
//} // namespace mapbox
# endif // MAPBOX_UTIL_VARIANT_HPP