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//clang 6.0.0
 
#include <memory>
 
class BigData
{
    // Only a builder can create data
	friend class Builder;
	BigData() = default;
public:
    // Move only
    BigData( BigData&& ) = default;
};
 
class Builder
{
    BigData Data;
public:
    const BigData&& Build() & { return std::move(Data); }
    // Functions to set up data go here
};
 
class Wrapper
{
    const BigData Data;
public:
    Wrapper( const BigData&& In ) : Data( std::move(In) ) {}
 
    // Functions to query data go here
};
 
std::unique_ptr<Wrapper> DoBuild()
{
    Builder b;
    // call functions on b to set up data here
    return std::make_unique<Wrapper>( b.Build() );
}
 
int main()
{
    auto wrapper = DoBuild();
}

prog.cpp: In constructor ‘Wrapper::Wrapper(const BigData&&)’:
prog.cpp:27:57: error: use of deleted function ‘constexpr BigData::BigData(const BigData&)’
     Wrapper( const BigData&& In ) : Data( std::move(In) ) {}
                                                         ^
prog.cpp:5:7: note: ‘constexpr BigData::BigData(const BigData&)’ is implicitly declared as deleted because ‘BigData’ declares a move constructor or move assignment operator
 class BigData
       ^~~~~~~

Standard output is empty