reorder()

template<std::size_t... Idx, product_type T>
requires ((Idx < size_v<T>) && ...)

constexpr auto kumi::reorder ( T &&  t )

inlineconstexpr

Reorder elements of a kumi::product_type.

This function does not participate in overload resolution if any Idx is outside [0, size_v<T>[.

Note

Nothing prevent the number of reordered index to be lesser or greater than t size or the fact they can appear multiple times.

reorder(tuple) works and is equivalent to reorder<>(tuple)

Template Parameters

Idx	Reordered index of elements

Parameters

t	kumi::product_type to reorder

Returns

A tuple equivalent to kumi::make_tuple(t[index<Idx>]...);

Helper type

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

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

Examples:

 
#include <kumi/kumi.hpp>
#include <iostream>
 
int main()
{
  auto values = kumi::tuple { 1, 'a', 0.1 };
 
  std::cout << values << "\n";
  std::cout << kumi::reorder<2,1,0>(values) << "\n";
  std::cout << kumi::reorder<2,1,0,1,2>(values) << "\n";
  std::cout << kumi::reorder<1,1>(values) << "\n";
}

 
#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<2,1,0>(values) << "\n";
}