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forked from Alepha/Alepha

I started a weird rewrite, but I'll likely abandon it.

But I'll keep this commit in my history, in case I want to try again.
This commit is contained in:
2023-10-31 01:44:34 -04:00
parent 3a5f6367b9
commit 4a74921cb8
2 changed files with 97 additions and 51 deletions

View File

@ -15,43 +15,42 @@ namespace Alepha::Hydrogen::IOStreams ::detail:: stream_state
class StreamState;
}
template< typename Tag, typename Type, auto Default >
class exports::StreamState
template< typename Type >
class exports::StreamState : boost::noncopyable
{
private:
static auto
index()
{
static const auto rv= std::ios::xalloc();
return rv;
}
const int index= std::ios::xalloc();
static Type *&
get_ptr( std::ios_base &ios, const int idx )
{
return reinterpret_cast< Type *& >( ios.pword( idx ) );
}
Type *&
get_ptr( std::ios_base &ios )
{
return reinterpret_cast< Type *& >( ios.pword( index() ) );
get_ptr( ios, index );
}
static void
destroy( std::ios_base &ios )
destroy( std::ios_base &ios, const int idx )
{
delete get_ptr( ios );
get_ptr( ios )= nullptr;
delete get_ptr( ios, idx );
get_ptr( ios, idx )= nullptr;
}
static void
callback_impl( const std::ios_base::event event, std::ios_base &ios, const int idx )
{
if( idx != index() ) throw std::logic_error( "Wrong index." );
if( event == std::ios_base::erase_event ) destroy( ios );
if( event == std::ios_base::erase_event ) destroy( ios, idx );
else if( event == std::ios_base::imbue_event )
{
// Nothing to do... until I develop locale support.
}
else if( event == std::ios_base::copyfmt_event )
{
get_ptr( ios )= new Type{ get( ios ) };
get_ptr( ios, idx )= new Type{ get( ios, idx ) };
}
}
@ -61,20 +60,20 @@ namespace Alepha::Hydrogen::IOStreams ::detail:: stream_state
return callback_impl( event, ios, idx );
}
static void
void
init( std::ios_base &ios )
{
if( not ios.iword( index() ) )
if( not ios.iword( idx ) )
{
ios.iword( index() )= 1;
ios.register_callback( callback, index() );
ios.register_callback( callback, idx );
}
auto *&ptr= get_ptr( ios );
auto *&ptr= get_ptr( ios, idx );
if( not ptr ) ptr= new Type{ Default() };
}
public:
static Type &
Type &
get( std::ios_base &ios )
{
init( ios );
@ -83,19 +82,20 @@ namespace Alepha::Hydrogen::IOStreams ::detail:: stream_state
struct Setter
{
StreamState *state;
const Type val;
friend std::ostream &
operator << ( std::ostream &os, const Setter &s )
{
StreamState::get( os )= s.val;
s.get( os )= s.val;
return os;
}
friend std::istream &
operator >> ( std::istream &is, const Setter &s )
{
StreamState::get( is )= s.val;
s.get( is )= s.val;
return is;
}
};

View File

@ -12,55 +12,101 @@ static_assert( __cplusplus > 2020'00 );
#include <Alepha/IOStreams/StreamState.h>
namespace Alepha::Hydrogen::IOStreams ::detail:: delimiters
namespace Alepha::Hydrogen::IOStreams ::detail:: delimiters_m
{
inline namespace exports {}
// Syntax I want to work:
//
// std::cout << someDelimiter;
// auto value= getDelimiter( someDelimiter, std::cin );
// std::cout << setDelimiter( someDelimiter, value );
struct Delimiter : boost::noncopyable
{
std::string current;
StreamState state;
explicit
Delimiter( const std::string current )
: current( current )
{
}
};
template< ConstexprString s >
using CreateDelimiter= void ( const DelimiterParamType< s > & );
template< typename T >
constexpr is_delimiter_v= false;
template< ConstexprString s >
constexpr is_delimiter_v< CreateDelimiter< s > >;
inline StaticValue< std::map< void (*)( const DelimiterBase & ), StreamState< Delim, std::string, globalDelimiter<
template< typename Delimiter >
using DelimiterStateByValue= StreamState< Delim, std::string, globalDelimiter< Delim > >;
inline namespace exports
{
enum { FieldDelimiter };
enum { RecordDelimiter };
}
Delimiter< "\t"_cs > FieldDelimiter;
Delimiter< "\t"_cs > FieldDelimiter2;
namespace C
{
const std::string defaultFieldDelimiter= "\t";
const char defaultRecordDelimiter= '\n';
static_assert( FieldDelimiter != FieldDelimiter2 );
Delimiter< "\n"_cs > RecordDelimiter;
}
namespace storage
{
inline StaticValue< std::optional< std::string > > globalFieldDelimiter;
inline StaticValue< std::optional< char > > globalRecordDelimiter;
template< auto Delim >
inline StaticValue< std::optional< std::string > > globalDelimiter;
}
inline std::string
globalFieldDelimiter()
template< auto Delim >
std::string &
globalDelimiter()
{
if( not storage::globalFieldDelimiter().has_value() ) storage::globalFieldDelimiter()= C::defaultFieldDelimiter;
if( not storage::globalDelimiter< Delim >().has_value() )
{
storage::globalDelimiter()= std::string{} + static_cast< char >( Delim );
}
assert( storage::globalDelimiter< Delim >().has_value() );
return storage::globalFieldDelimiter().value();
}
namespace exports
{
inline void
setGlobalFieldDelimiter( const std::string delim )
template< auto Delim >
void
setGlobaDelimiter( const std::string delim )
{
storage::globalFieldDelimiter()= delim;
storage::globalDelimiter< Delim >()= delim;
}
}
inline char
globalRecordDelimiter()
{
if( not storage::globalRecordDelimiter().has_value() ) storage::globalRecordDelimiter()= C::defaultRecordDelimiter;
return storage::globalRecordDelimiter().value();
}
template< auto Delim >
using DelimiterStateByValue= StreamState< Delim, std::string, globalDelimiter< Delim > >;
using FieldDelimiterState= StreamState< decltype( FieldDelimiter ), std::string, globalFieldDelimiter >;
inline std::ostream &
operator << ( std::ostream &os, decltype( FieldDelimiter ) )
template< typename DelimType >
using DelimiterState= StreamState< Delim, std::string, globalDelimiter >;
struct DelimWrap
{
template< typename Delim >
Delim val;
};
std::ostream &
operator << ( std::ostream &os, auto DelimVal )
{
return os << FieldDelimiterState::get( os );
return os << DelimiterState< decltype( DelimVal ) >::get( os );
}
namespace exports
@ -122,7 +168,7 @@ namespace Alepha::Hydrogen::IOStreams ::detail:: delimiters
}
}
namespace Alepha::Hydrogen::IOStreams::inline exports::inline delimiters
namespace Alepha::Hydrogen::IOStreams::inline exports::inline delimiters_m
{
using namespace detail::delimiters::exports;
using namespace detail::delimiters_m::exports;
}