1// Copyright 2016-2024 Antony Polukhin
2
3// Distributed under the Boost Software License, Version 1.0.
4// (See the accompanying file LICENSE_1_0.txt
5// or a copy at <http://www.boost.org/LICENSE_1_0.txt>.)
6
7//[pfr_example_get
8/*`
9 The following example shows how to access structure fields by index using [funcref boost::pfr::get].
10
11 Let's define some structure:
12*/
13#include <boost/pfr/core.hpp>
14
15struct foo { // defining structure
16 int some_integer;
17 char c;
18};
19
20/*`
21 We can access fields of that structure by index:
22*/
23foo f {.some_integer: 777, .c: '!'};
24auto& r1 = boost::pfr::get<0>(val&: f); // accessing field with index 0, returns reference to `foo::some_integer`
25auto& r2 = boost::pfr::get<1>(val&: f); // accessing field with index 1, returns reference to `foo::c`
26//] [/pfr_example_get]
27
28
29int main() {
30 if (r1 != 777) return 1;
31 if (r2 != '!') return 2;
32
33 r1 = 42;
34 r2 = 'A';
35
36 if (r1 != 42) return 3;
37 if (r2 != 'A') return 4;
38 if (f.some_integer != 42) return 5;
39 if (f.c != 'A') return 6;
40
41 return 0;
42}
43

source code of boost/libs/pfr/example/get.cpp