"Doug Gregor" <dgregor@cs.indiana.edu> wrote
On Jul 22, 2004, at 8:08 AM, Arkadiy Vertleyb wrote:
[snip]
It could just be called BOOST_DECLTYPE, with the caveat that it doesn't act quite perfectly for variables. Frankly, I couldn't care much less about variables: you rarely need the type of those, although I could easily contrive cases.
I want variables! In context of my physical quantities library types resulting from calcs are computed in non-trivial ways. If the programmer has a complicated calculation then declaring a variable may force a scaling q_area::mm2 a; q_length:: mm b; q_length::m c = a / b; In the above, the temporary result of a / b will be divided by 1000 in the assign to cc, because the programmer has forced this by the l_value assignment,but: auto c = a / b; Here, the resulting units of the temporary are automatically computed., no scaling. In this case units of millimetres( I think... all these assertions require manual checking) would be the auto type, but the programmer doesnt need to worry about it. ie every non-auto assignment represents a potential loss in speed and accuracy. This is a major potential useage of the mechanism in my physical quantities library. FWIW I am very interested in BOOST_TYPEOF but unfortunately dont have time to investigate for a couple of weeks. regards Andy Little