reorder_fields()

template<field_name... Name, product_type Tuple>
requires ( requires { get<Name>(std::declval<Tuple>()); } && ... )

constexpr auto kumi::reorder_fields ( Tuple &&  t )

inlineconstexpr

Reorder elements of a kumi::record.

This function does not participate in overload resolution if the names are not in T

Note

Nothing prevent the number of reordered names to be lesser or greater than t size or the fact they can appear multiple times if it is applied on a named tuple.

Template Parameters

Name	Reordered names of elements

Parameters

t	kumi::product_type to reorder

Returns

A product type equivalent to product_type(t[index<Idx>]...);

Helper type

namespace kumi::result
{
  template<product_type Tuple,std::size_t... Idx> struct reorder_fields;
 
  template<product_type Tuple,std::size_t... Idx>
  using reorder_fields_t = typename reorder_fields<Tuple,Idx...>::type;
}

Computes the return type of a call to kumi::reorder_fields

Example

 
#include <kumi/kumi.hpp>
#include <iostream>
 
int main()
{
  using namespace kumi::literals;
 
  auto values = kumi::record { "a"_f = 1, "b"_f = 'a', "c"_f = 0.1 };
 
  std::cout << values << "\n";
  std::cout << kumi::reorder_fields<"b"_f,"a"_f,"c"_f>(values) << "\n";
}