1
0
forked from Alepha/Alepha

Bring in type-lisp from my scratch projects.

This commit is contained in:
2023-10-09 20:33:35 -04:00
parent df489cdb97
commit 273b9eb8b5

92
type_lisp.h Normal file
View File

@ -0,0 +1,92 @@
static_assert( __cplusplus > 2020'00 );
#pragma once
#include <type_traits>
namespace Alepha::inline Cavorite ::detail:: type_lisp
{
inline namespace exports {}
namespace exports
{
template< typename ... > struct TypeList {};
using Nil= TypeList<>;
template< typename T >
constexpr bool is_nil_v= std::is_same_v< T, Nil >;
}
template< typename T >
constexpr bool is_type_list_v= false;
template< typename ... Args >
constexpr bool is_type_list_v< TypeList< Args... > >{ true };
namespace exports
{
template< typename Type >
concept TypeListType= is_type_list_v< Type >:
}
template< typename T >
struct tuple_from_list;
namespace exports
{
template< typename List >
using tuple_from_list_t= typename tuple_from_list< List >::type;
}
template< typename ... Members >
struct tuple_from_list< TypeList< Members... > >
{
using type= std::tuple< Members... >;
};
template< typename List >
struct car_impl { using type= Nil; };
template< typename Arg0, typename ... Args >
struct car_impl< TypeList< Arg0, Args... > >
{
using type= Arg0;
};
template< typename List >
struct cdr_impl { using type= Nil; };
template< typename Arg0, typename ... Args >
struct cdr_impl< TypeList< Arg0, Args... > >
{
using type= TypeList< Args... >;
};
namespace exports
{
template< typename List >
using car_t= typename car_impl< List >::type;
template< typename List >
using cdr_t= typename cdr_impl< List >::type;
}
namespace exports
{
template< typename List, typename Element >
constexpr bool list_contains_v=
std::is_same_v< Element, car_t< List > >
or
list_contains_v< cdr_t< List >, Element >;
template< typename Element >
constexpr bool list_contains_v< Nil, Element >{};
}
}
namespace Alepha::Cavorite::inline exports::inline type_lisp
{
using namespace detail::type_lisp::exports;
}