rem: virtual string description(void) const { return("Interface for mp3 decoders and encoders that support input/output using standard streams."); }
add: virtual std::string description(void) const { return("Interface for mp3 decoders and encoders that support input/output using standard streams."); }
context:   virtual string description(void) const { return("Interface for mp3 decoders and encoders that support input/output using standard streams."); }