1
0
forked from Alepha/Alepha
Files
Alepha/comparisons.h
ADAM David Alan Martin 9c9ed65312 I think this makes capabilities much simpler and more reliable.
But the capabilities are now limited to a single param -- Time to change that?
2024-01-27 04:21:27 -05:00

440 lines
12 KiB
C++

static_assert( __cplusplus > 2020'99 );
#pragma once
#include <Alepha/Alepha.h>
#include <type_traits>
#include <Alepha/Meta/dep_value.h>
#include <Alepha/Capabilities.h>
#include <Alepha/Meta/overload.h>
namespace Alepha::Hydrogen
{
inline namespace exports { inline namespace comparisons_m {} }
namespace detail::comparisons_m
{
inline namespace exports {}
using namespace Meta::exports::template_overload;
struct comparable {};
namespace exports
{
using detail::comparisons_m::comparable;
}
template< typename T >
constexpr bool has_comparable_capability_v= HasCapability< std::decay_t< T >, comparable >;
// Spaceship lens support
template< typename T, typename= void >
struct has_spaceship_lens_member : std::false_type {};
template< typename T >
struct has_spaceship_lens_member< T, std::void_t< decltype( std::declval< const T & >().spaceship_lens() ) > > : std::true_type {};
template< typename T >
constexpr bool has_spaceship_lens_member_v= has_spaceship_lens_member< T >::value;
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< has_spaceship_lens_member_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
spaceship_lens( T &t )
{
return t.spaceship_lens();
}
template< typename T, typename= void >
struct supports_spaceship_lens : std::false_type {};
template< typename T >
struct supports_spaceship_lens< T, std::void_t< decltype( spaceship_lens( std::declval< const T & >() ) ) > > : std::true_type {};
template< typename T >
constexpr bool supports_spaceship_lens_v= supports_spaceship_lens< T >::value;
template< typename T >
constexpr decltype( auto )
make_spaceship_lens( T &t )
{
if constexpr( supports_spaceship_lens_v< T > ) return spaceship_lens( t );
//else if constexpr( supports_default_lens_v< T > ) return default_lens( t );
else static_assert( Meta::dep_value< false, T > );
}
// Value lens support
template< typename T, typename= void >
struct has_value_lens_member : std::false_type {};
template< typename T >
struct has_value_lens_member< T, std::void_t< decltype( std::declval< const T & >().value_lens() ) > > : std::true_type {};
template< typename T >
constexpr bool has_value_lens_member_v= has_value_lens_member< T >::value;
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< has_value_lens_member_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
value_lens( T &t )
{
return t.value_lens();
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< supports_spaceship_lens_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
value_lens( T &t )
{
return spaceship_lens( t );
}
template< typename T, typename= void >
struct supports_value_lens : std::false_type {};
template< typename T >
struct supports_value_lens< T, std::void_t< decltype( value_lens( std::declval< const T & >() ) ) > > : std::true_type {};
template< typename T >
constexpr bool supports_value_lens_v= supports_value_lens< T >::value;
template< typename T >
constexpr decltype( auto )
make_value_lens( T &t )
{
if constexpr( supports_value_lens_v< T > ) return value_lens( t );
//else if constexpr( supports_default_lens_v< T > ) return default_lens( t );
else static_assert( Meta::dep_value< false, T > );
}
// Equality Lens support
template< typename T, typename= void >
struct has_equality_lens_member : std::false_type {};
template< typename T >
struct has_equality_lens_member< T, std::void_t< decltype( std::declval< const T & >().equality_lens() ) > > : std::true_type {};
template< typename T >
constexpr bool has_equality_lens_member_v= has_equality_lens_member< T >::value;
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< has_equality_lens_member_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
equality_lens( T &t )
{
return t.equality_lens();
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< supports_value_lens_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
equality_lens( T &t )
{
return value_lens( t );
}
template< typename T, typename= void >
struct supports_equality_lens : std::false_type {};
template< typename T >
struct supports_equality_lens< T, std::void_t< decltype( equality_lens( std::declval< const T & >() ) ) > > : std::true_type {};
template< typename T >
constexpr bool supports_equality_lens_v= supports_equality_lens< T >::value;
template< typename T >
constexpr decltype( auto )
make_equality_lens( T &t )
{
if constexpr( supports_equality_lens_v< T > ) return equality_lens( t );
//else if constexpr( supports_default_lens_v< T > ) return default_lens( t );
else static_assert( Meta::dep_value< false, T > );
}
// Strict weak order lens support
template< typename T, typename= void >
struct has_strict_weak_order_lens_member : std::false_type {};
template< typename T >
struct has_strict_weak_order_lens_member< T, std::void_t< decltype( std::declval< const T & >().strict_weak_order_lens() ) > > : std::true_type {};
template< typename T >
constexpr bool has_strict_weak_order_lens_member_v= has_strict_weak_order_lens_member< T >::value;
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< has_strict_weak_order_lens_member_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
strict_weak_order_lens( T &t )
{
return t.strict_weak_order_lens();
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
typename= std::enable_if_t< supports_value_lens_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr decltype( auto )
strict_weak_order_lens( T &t )
{
return value_lens( t );
}
template< typename T, typename= void >
struct supports_strict_weak_order_lens : std::false_type {};
template< typename T >
struct supports_strict_weak_order_lens< T, std::void_t< decltype( strict_weak_order_lens( std::declval< const T & >() ) ) > > : std::true_type {};
template< typename T >
constexpr bool supports_strict_weak_order_lens_v= supports_strict_weak_order_lens< T >::value;
template< typename T >
constexpr decltype( auto )
make_strict_weak_order_lens( T &t )
{
if constexpr( supports_strict_weak_order_lens_v< T > ) return strict_weak_order_lens( t );
//else if constexpr( supports_default_lens_v< T > ) return default_lens( t );
else static_assert( Meta::dep_value< false, T > );
}
// Operator support:
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator == ( const T &lhs, const T &rhs )
{
return make_equality_lens( lhs ) == make_equality_lens( rhs );
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator != ( const T &lhs, const T &rhs )
{
return make_equality_lens( lhs ) != make_equality_lens( rhs );
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator < ( const T &lhs, const T &rhs )
{
return make_strict_weak_order_lens( lhs ) < make_strict_weak_order_lens( rhs );
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator > ( const T &lhs, const T &rhs )
{
return make_strict_weak_order_lens( lhs ) > make_strict_weak_order_lens( rhs );
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator <= ( const T &lhs, const T &rhs )
{
return make_strict_weak_order_lens( lhs ) <= make_strict_weak_order_lens( rhs );
}
template
<
typename T,
typename= std::enable_if_t< has_comparable_capability_v< T > >,
overload< __LINE__ > = nullptr
>
constexpr bool
operator >= ( const T &lhs, const T &rhs )
{
return make_strict_weak_order_lens( lhs ) >= make_strict_weak_order_lens( rhs );
}
template< typename ... Args >
struct magma_hook
{
std::tuple< Args... > view;
};
namespace exports
{
template< typename ... Args >
constexpr auto
ordering_magma( Args && ... args )
{
return magma_hook< Args... >{ std::tie( std::forward< Args >( args )... ) };
}
}
// TODO: Sort out the linear-trichotomous problem.
template< typename comp, std::size_t index= 0, typename ... Args >
constexpr bool
compOp( const std::tuple< Args... > &lhs, const std::tuple< Args... > &rhs )
{
if constexpr( index == sizeof...( Args ) ) return false;
else
{
const auto &l= std::get< index >( lhs );
const auto &r= std::get< index >( rhs );
if( comp{}( l, r ) ) return true;
else if( comp{}( r, l ) ) return false;
return compOp< comp, index + 1 >( lhs, rhs );
}
}
template< typename ... Args >
constexpr bool
operator < ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return compOp< std::less<> >( lhs.view, rhs.view );
}
template< typename ... Args >
constexpr bool
operator > ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return compOp< std::greater<> >( lhs.view, rhs.view );
}
template< typename comp, std::size_t index= 0, typename ... Args >
constexpr bool
comp_eqOp( const std::tuple< Args... > &lhs, const std::tuple< Args... > &rhs )
{
if constexpr( index == sizeof...( Args ) ) return true;
else
{
const auto &l= std::get< index >( lhs );
const auto &r= std::get< index >( rhs );
const bool first_pass= comp{}( l, r );
if( first_pass and comp{}( r, l ) ) return comp_eqOp< comp, index + 1 >( lhs, rhs );
return first_pass;
}
}
template< typename ... Args >
constexpr bool
operator <= ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return comp_eqOp< std::less_equal<> >( lhs.view, rhs.view );
}
template< typename ... Args >
constexpr bool
operator >= ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return comp_eqOp< std::greater_equal<> >( lhs.view, rhs.view );
}
template< std::size_t index= 0, typename ... Args >
constexpr bool
eq( const std::tuple< Args... > &lhs, const std::tuple< Args... > &rhs )
{
if constexpr( index == sizeof...( Args ) ) return true;
else
{
const auto &l= std::get< index >( lhs );
const auto &r= std::get< index >( rhs );
return ( l == r ) and eq< index + 1 >( lhs, rhs );
}
}
template< typename ... Args >
constexpr bool
operator == ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return eq( lhs.view, rhs.view );
}
template< std::size_t index= 0, typename ... Args >
constexpr bool
ne( const std::tuple< Args... > &lhs, const std::tuple< Args... > &rhs )
{
if constexpr( index == sizeof...( Args ) ) return false;
else
{
const auto &l= std::get< index >( lhs );
const auto &r= std::get< index >( rhs );
return l != r and ne< index + 1 >( lhs, rhs );
}
}
template< typename ... Args >
constexpr bool
operator != ( const magma_hook< Args... > &lhs, const magma_hook< Args... > &rhs )
{
return ne( lhs, rhs );
}
}
namespace exports::comparisons_m
{
using namespace detail::comparisons_m::exports;
}
}