Re: [Boost-users] [fusion] deduce type of resulting vector from a transformation

Am 10.10.2010 12:02, schrieb alfC:

Hi,

(I keep struggling with Boos.Fusion.)

How do I deduce the type of the vector resulting from the transformation of another vector?

I have a source vector of different types, e.g. vectorsi::length, quantitysi::mass, quantitysi::time

...

and I have a transformation that is well defined and returns another type depending on the original type. The question is how do I generate a vector type that is the result of the given transformation. I though that result_of::transform was the function to obtain the result but it turns not because it returns a type transform_view instead of a vector.

vector< ... > v1; T? v2(transform(v1, transformation()));

i.e. what is the type of T as a fusion::vector as deduced from the type of v1 and the transformation type? -- Thank you, Alfredo--

You can generate a vector from an arbitrary fusion sequence using the conversion metafunction: http://www.boost.org/doc/libs/1_44_0/libs/fusion/doc/html/fusion/container/c... fusion::result_of::as_vector< fusion::result_of::transform< v1, transformation >::type

::type v2(fusion::transform(v1, transformation()));

-Christopher