Jeremy Maitin-Shepard wrote:
One of the significant advantages to using formatting facilities like *printf or Boost Format is that messages with embedded value placement indicators can be stored as a single string, which makes translation of such message strings much, much easier. Thus, much of the benefit of such a facility is lost when the ability to represent message strings as single strings is lost.
I know that, it's really common sense. I'm only thinking of using str_stream() for debugging/logging. (p.s. - indeed, I should have specified this in the original post ;)) In this case, it does make a lot of sense (at least to me). Just think how easy it is to say something like: throw std::runtime_error(str_stream() << "invalid line at idx " << idx); as opposed to something like throw std::runtime_error(io::str(format("invalid line at idx %1%) % idx))); I think the former is more readable. It's not just that. It's also the fact that str_stream is **lightweight**. Have you taken a look at the implementation of boost::format? Don't get me wrong - I love boost::format. In fact I use it a lot. But for simple things I use simple classes. As a side note, you can also use it like this: std::string s = str_stream(idx); Best, John