if (fb_.is_open() || istream::off_type(is.tellg()) > 0)
lyxerr[Debug::LYXLEX] << "Error in LyXLex::setFile: "
"file or stream already set." << endl;
if (fb_.is_open() || istream::off_type(is.tellg()) > 0)
lyxerr[Debug::LYXLEX] << "Error in LyXLex::setFile: "
"file or stream already set." << endl;