Detailed Description

template<typename... Ts>
struct stan::return_type< Ts >

Template metaprogram to calculate the base scalar return type resulting from promoting all the scalar types of the template parameters to the least type to which all the base types of the arguments are assignable.

The metaprogram can take an arbitrary number of template parameters.

Complex numbers (instances of std::complex<T>) are considered scalars. All C++ primitive types (except long double) are automatically promoted to double.

The set of autodiff types is defined to be the smallest such that

var is an autodiff type,
fvar<double> is an autodiff type, and
fvar<T> is an autodiff type if T is an autodiff type.

The set of scalar types is defined to be the smallest such that

double and long double are scalar types,
T is a scalar type if T is an autodiff type,
complex<double> is a scalar type, and
complex<T> is a scalar type if T is an autodiff type.

The assignability relation among scalar types is defined to be the smallest such that

double is assignable to any type T,
T1 is assignable to std::complex<T2> if T1 is assignable to
T2, and
std::complex<T1> is assignable to std::complex<T2> if T1 is assignable to T2.

Example usage:

return_type_t<int, double, float> is double
return_type_t<double, var> is var

Template Parameters

Ts	sequence of input types

Definition at line 207 of file return_type.hpp.

#include <return_type.hpp>

Inheritance diagram for stan::return_type< Ts >:

Public Types
using	type = double

The documentation for this struct was generated from the following file:

stan/math/prim/meta/return_type.hpp

Detailed Description

Public Types