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Merged
VeaaC merged 2 commits into from
Apr 14, 2026
Merged

MINOR: adding Reader/Writer std::optional variants, same as boost::op… #258

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019729d
MINOR: adding Reader/Writer std::optional variants, same as boost::op…
Apr 13, 2026
cfef398
added tests
Apr 13, 2026
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3 changes: 0 additions & 3 deletions flatdata-cpp/benchmark/main.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -215,17 +215,14 @@ main( int argc, char** argv )
}
else if ( args.at( "lookup" ).asBool( ) )
{
size_t num_runs = args.at( "--num-runs" ).asLong( );
call_for_graph< DoLookup >( argv[ 2 ], num_nodes, num_runs );
}
else if ( args.at( "bfs" ).asBool( ) )
{
size_t num_runs = args.at( "--num-runs" ).asLong( );
call_for_graph< DoBFS >( argv[ 2 ], num_nodes, num_runs );
}
else if ( args.at( "dijkstra" ).asBool( ) )
{
size_t num_runs = args.at( "--num-runs" ).asLong( );
call_for_graph< DoDijkstra >( argv[ 2 ], num_nodes, num_runs );
}
}
Expand Down
15 changes: 15 additions & 0 deletions flatdata-cpp/include/flatdata/internal/Reader.h
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Expand Up @@ -13,6 +13,7 @@
#include <boost/optional/optional_io.hpp>

#include <cstring>
#include <optional>
#include <utility>

#include <flatdata/MemoryDescriptor.h>
Expand Down Expand Up @@ -154,6 +155,20 @@ struct Reader< Tagged< T, INVALID_VALUE >, offset, num_bits, struct_size_bytes >
return boost::optional< U >( Reader< T, offset, num_bits, struct_size_bytes >{ data } );
}
}

template < typename U >
operator std::optional< U >( ) const
{
boost::optional< U > bopt = static_cast< boost::optional< U > >( *this );
if ( bopt )
{
return *bopt;
}
else
{
return std::nullopt;
}
}
};

} // namespace flatdata
26 changes: 26 additions & 0 deletions flatdata-cpp/include/flatdata/internal/Writer.h
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Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,7 @@

#include <cassert>
#include <type_traits>
#include <optional>

namespace flatdata
{
Expand Down Expand Up @@ -125,6 +126,19 @@ struct Writer< Tagged< T, INVALID_VALUE >, offset, num_bits, struct_size_bytes >
return Reader< Tagged< T, INVALID_VALUE >, offset, num_bits >{ data };
}

operator std::optional< T >( ) const
{
boost::optional< T > bopt = static_cast< boost::optional< T > >( *this );
if ( bopt )
{
return *bopt;
}
else
{
return std::nullopt;
}
}

Writer&
operator=( T t )
{
Expand All @@ -143,6 +157,18 @@ struct Writer< Tagged< T, INVALID_VALUE >, offset, num_bits, struct_size_bytes >
{
Writer< T, offset, num_bits >{ data } = INVALID_VALUE;
}
return *this;
}

Writer&
operator=( std::optional< T > t )
{
boost::optional< T > bopt;
if ( t )
{
bopt = *t;
}
return *this = bopt;
}
};

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20 changes: 19 additions & 1 deletion flatdata-cpp/test/StructTest.cpp
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Expand Up @@ -43,54 +43,72 @@ TEST_CASE( "Invalid values are handled", "[Struct]" )
REQUIRE( static_cast< bool >( writer.invalid_zero ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_zero )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_zero )
== std::optional< int8_t >( 10 ) );
REQUIRE( *reader.invalid_zero == 10 );
REQUIRE( static_cast< bool >( reader.invalid_zero ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_zero )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_zero )
== std::optional< int8_t >( 10 ) );

writer.invalid_zero = 0;
REQUIRE( *writer.invalid_zero == 0 );
REQUIRE( static_cast< bool >( writer.invalid_zero ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_zero ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_zero ) == std::nullopt );
REQUIRE( *reader.invalid_zero == 0 );
REQUIRE( static_cast< bool >( reader.invalid_zero ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_zero ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_zero ) == std::nullopt );

writer.invalid_min_int = 10;
REQUIRE( *writer.invalid_min_int == 10 );
REQUIRE( static_cast< bool >( writer.invalid_min_int ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_min_int )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_min_int )
== std::optional< int8_t >( 10 ) );
REQUIRE( *reader.invalid_min_int == 10 );
REQUIRE( static_cast< bool >( reader.invalid_min_int ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_min_int )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_min_int )
== std::optional< int8_t >( 10 ) );

writer.invalid_min_int = -128;
REQUIRE( *writer.invalid_min_int == -128 );
REQUIRE( static_cast< bool >( writer.invalid_min_int ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_min_int ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_min_int ) == std::nullopt );
REQUIRE( *reader.invalid_min_int == -128 );
REQUIRE( static_cast< bool >( reader.invalid_min_int ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_min_int ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_min_int ) == std::nullopt );

writer.invalid_max_int = 10;
REQUIRE( *writer.invalid_max_int == 10 );
REQUIRE( static_cast< bool >( writer.invalid_max_int ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_max_int )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_max_int )
== std::optional< int8_t >( 10 ) );
REQUIRE( *reader.invalid_max_int == 10 );
REQUIRE( static_cast< bool >( reader.invalid_max_int ) == true );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_max_int )
== boost::optional< int8_t >( 10 ) );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_max_int )
== std::optional< int8_t >( 10 ) );

writer.invalid_max_int = 127;
REQUIRE( *writer.invalid_max_int == 127 );
REQUIRE( static_cast< bool >( writer.invalid_max_int ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( writer.invalid_max_int ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( writer.invalid_max_int ) == std::nullopt );
REQUIRE( *reader.invalid_max_int == 127 );
REQUIRE( static_cast< bool >( reader.invalid_max_int ) == false );
REQUIRE( static_cast< boost::optional< int8_t > >( reader.invalid_max_int ) == boost::none );
REQUIRE( static_cast< std::optional< int8_t > >( reader.invalid_max_int ) == std::nullopt );
}

TEST_CASE( "Invalid values can be converted to string", "[Struct]" )
Expand All @@ -102,4 +120,4 @@ TEST_CASE( "Invalid values can be converted to string", "[Struct]" )
invalid_max_int : 0,
})";
REQUIRE( ( *data ).to_string( ) == EXPECTED );
}
}