Re: [Boost-users] Boost.Units Example: Convert between nautical mile and imperial foot

Subject: Re: [Boost-users] Boost.Units Example: Convert between nautical mile and imperial foot
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2018-09-27 14:06:08

AMDG

On 09/26/2018 08:29 PM, Gavin Lambert via Boost-users wrote:
> 
> Oddly, given these:
> 
> BOOST_UNITS_DEFAULT_CONVERSION(imperial::length_base_unit, si::length);
> BOOST_UNITS_DEFAULT_CONVERSION(nautical::length_base_unit, si::length);
> 
> Only one of these two lines actually needs to be defined in order to
> make both direct conversions (ft -> nmi and nmi -> ft) compile.  Given
> that all three base units are independent, how does this work?
> 

If you have only the first, then
ft -> nmi is reduced to meters -> nmi which
can be handled directly.  The library doesn't
care about the direction of the conversion.

In Christ,
Steven Watanabe