[ublas] promote_traits deficiency

From: Neal Becker (ndbecker2_at_[hidden])
Date: 2006-05-01 13:51:58

I've run into an issue with promote_traits.  IIUC, it really isn't an issue
with ublas, per se, but maybe with std::complex.  Still, perhaps we can
address it.

It seems that constructs like

promote_traits<std::complex<long double>, double>

don't work, because they eventually do something like:

typeof (std::complex<long double> + double),

which unfortunately seem to be undefined.