I'm using Boost.Format as a simple way to create strings to pass to exception constructors and primitive logging output during debugging (Windows' OutputDebugString). I see that the format object can be inserted into a stream, easily. But, with arguments, it's awkward to convert it to a string -- you need extra parens around the whole thing. Is there some good reason why there is no implicit conversion to string? E.g. string message= boost.format("blah") % argument % errorcode; OutputDebugStringA (message.c_str()); throw std::runtime_error (message); Or, is there some simple way that I'm missing? Thanks, --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.