Hello, EventTypeis a string and CurrencyEventPtr is just shared_ptr. CurrencyCouple is just a class, nothing special. typdef std::string EventType; typedef boost::shared_ptr<CurrencyEvent> CurrencyEventPtr; Thanks for help ___________________________________________________________ This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and delete this e-mail. Any unauthorised copying, disclosure or distribution of the material in this e-mail is prohibited. Please refer to http://www.bnpparibas.co.uk/en/information/legal_information.asp?Code=ECAS-8... for additional disclosures.