[Boost-users] [format] %d, %u etc. with (unsigned) char types

From: Luke Elliott (luke_elliott_at_[hidden])
Date: 2006-04-13 13:49:38

I couldn't find anything on this in the list archives or the format 
docs, but it seems likely to have been asked before so apologies if that 
is the case.

I would expect something like:

boost::format fmt("%d");

fmt % char(0);
std::cout << fmt;

to output "0" given that %d is explicitly specified. This isn't the case 
  (with VC++ 7.1 and GCC 3.4 at least, and presumably all others given 
this is normal stream behaviour).

Obviously it can be worked around by casting to a non-char type, but 
that seems a shame given the nature of the library and not having to 
worry about type-safety too much.

So, is this by design or accident? If not by design, would it be 
possible to change the behaviour (specialisation somewhere for 
(unsigned) char types or something??)?

Thanks in advance

Luke Elliott.