RE: [boost] 3-state boolean type

From: Petr Kocmid (pkocmid_at_[hidden])
Date: 2002-08-03 20:57:29

> > Maybe some type traits should be added for such a 3-state too.
> What traits do we need?

Me sees is_convertible<bool, tribool> comes handy.

How should we do input and output with tribool? With value hidden, people
certainly want basic_istream operator>> and << for basic_ostream. More,
without possibility to convert to numeric type one would need needs a locale
facets for tribool.
So, some stream crafting similar as in boost quaternion comes to question
(Quaternion i/o is modelled after std::complex I believe).

Petr Kocmid