Method operator++

tests/catch.hpp:6812–6821

        }

        auto operator++() -> TokenStream & {
            if( m_tokenBuffer.size() >= 2 ) {
                m_tokenBuffer.erase( m_tokenBuffer.begin() );
            } else {
                if( it != itEnd )
                    ++it;
                loadBuffer();
            }
            return *this;
        }
    };

    class ResultBase {