rem: if ( !subtype || !*subtype ) return 0;
context:   const KMail::BodyPartFormatter * createForMessage( const char * subtype ) {    if ( !subtype || !*subtype )      return 0;    if ( qstricmp( subtype, "rfc822" ) == 0 )      return MessageRfc822BodyPartFormatter::create();    return AnyTypeBodyPartFormatter::create();  }