On 27 March 2014 23:56, Luke Allardyce wrote: > It looks like the new standard also requires the precision to be > ignored for hexfloat > >>For conversion from a floating-point type, if floatfield != (ios_base::fixed >>| ios_base:: scientific), str.precision() is specified as precision in the >>conversion specification. Otherwise, no precision is specified.
Thanks for pointing out that difference. We'll need a test for that. > Also the old standard seems to require that ios_base::fixed | > ios_base::scientific (or any other combination) falls through to the > uppercase test; I was trying to use abi_tag for a solution as not only > would two versions of _S_format_float be necessary, but also num_get > due to the pre-instantiated templates for <char> and <wchar>, which > led me to http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60642. It might > just be more trouble than it's worth. I don't think we need to worry about that, if I understand correctly the combination of fixed|scientific has unspecified behaviour in C++03, so we can make our implementation do exactly what it does in C++11.