Method empty

CvPlot/ext/catch2/inc/catch.hpp:492–492

        SourceLineInfo& operator = ( SourceLineInfo&& ) noexcept = default;

        bool empty() const noexcept { return file[0] == '\0'; }
        bool operator == ( SourceLineInfo const& other ) const noexcept;
        bool operator < ( SourceLineInfo const& other ) const noexcept;