Re: [Boost-users] [units] Creating a velocity unit

AMDG On 02/21/2013 01:56 PM, Ryan wrote:

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Yes, that's what I meant, but now that I see it written out, it's wrong because decltype keeps the const qualifier. You need the behavior of the non-standard typeof operator. BOOST_TYPEOF should work.

quantity(2.3 * nautical_mile);

I tried this and it works. Is there a method, template or macro that lets me create the following two line like BOOST_UNITS_STATIC_CONSTANT?

typedef metric::nautical_mile_base_unit::unit_type nautical_mile_unit; static const nautical_mile_unit nautical_mile;

That way I don't have to create a name for the type and only use BOOST_TYPEOF if I need the type from the global constant.

There is no such macro (and it can't be done by any other means). If you want one, there's nothing stopping you from writing one yourself. Anything that I could write would need to be generic enough that it wouldn't save you anything. Also, I should point out that you don't need the intermediate typedef. BOOST_UNITS_STATIC_CONSTANT(nautical_mile, metric::nautical_mile_base_unit::unit_type); will work just fine. In Christ, Steven Watanabe