push_front()

template<concepts::product_type T, typename V>

auto kumi::push_front ( T && t, V && v )

inlinenodiscardconstexpr

Constructs a product type by adding a value v at the beginning of t.

Parameters

t	Base product type
v	Value to insert in front of t

Returns

A product type composed of v followed by all elements of t in order.

On record types, this function operates on elements as if they were ordered. The considered order is the order of declaration.

Helper type

namespace kumi::result
{
  template<product_type T, typename V> struct push_front;
 
  template<product_type T, typename V>
  using push_front_t = typename push_front<T,V>::type;
}

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

Examples:

Tuple:

#include <kumi/kumi.hpp>
#include <iostream>
 
int main()
{
  std::cout << kumi::push_front( kumi::tuple{}, 63.21)  << "\n";
 
  kumi::tuple t{1,2.,3.4f};
  std::cout << t                          << "\n";
  std::cout << kumi::push_front(t, 'Z')   << "\n";
}

Record:

#include <kumi/kumi.hpp>
#include <iostream>
 
int main()
{
  using namespace kumi::literals;
 
  std::cout << kumi::push_front( kumi::record{}, "a"_id = 63.21)  << "\n";
 
  kumi::record t{"a"_id = 1,"b"_id = 2.,"c"_id = 3.4f};
  std::cout << t                          << "\n";
  std::cout << kumi::push_front(t, "d"_id = 'Z')   << "\n";
}