xtd::expressions::placeholders< count > Struct Template Reference

Definition

template<size_t count>
struct xtd::expressions::placeholders< count >

Generates a set of positional placeholders that can be decomposed using structured bindings to build readable and composable expression templates.

Namespace

xtd::expressions

Header

#include <xtd/expressions/placeholders>

Library

xtd.core

Examples

The following example shows how to use xtd::expressions::expression::placeholders.

#include <xtd/xtd>
 
auto main() -> int {
  //auto expr1 = [](auto&& operand_one, auto&& operand_two) {return operand_one + operand_two;};
  auto [operand_one, operand_two] = placeholders<2>();
  auto expr1 = operand_one + operand_two;
  println("expr1 result => {}", expr1(10, 20));
  //auto expr2 = [](auto&& _1, auto&& _2) {return _1 + _2;};
  auto expr2 = _1 + _2;
  println("expr2 result => {}", expr2(10, 20));
}
 
// This code produces the following output :
//
// expr1 result => 30
// expr2 result => 30

Public Member Functions
template<size_t index>
constexpr auto	get () const noexcept

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

• xtd.core/include/xtd/expressions/placeholders.hpp