使用boost pfr 遍历结构体

3rd/pfr/example/get.cpp

@@ -0,0 +1,42 @@
+// Copyright 2016-2023 Antony Polukhin
+
+// Distributed under the Boost Software License, Version 1.0.
+// (See the accompanying file LICENSE_1_0.txt
+// or a copy at <http://www.boost.org/LICENSE_1_0.txt>.)
+
+//[pfr_example_get
+/*`
+    The following example shows how to access structure fields by index using [funcref boost::pfr::get].
+
+    Let's define some structure:
+*/
+#include <boost/pfr/core.hpp>
+
+struct foo {            // defining structure
+    int some_integer;
+    char c;
+};
+
+/*`
+    We can access fields of that structure by index:
+*/
+foo f {777, '!'};
+auto& r1 = boost::pfr::get<0>(f); // accessing field with index 0, returns reference to `foo::some_integer`
+auto& r2 = boost::pfr::get<1>(f); // accessing field with index 1, returns reference to `foo::c`
+//] [/pfr_example_get]
+
+
+int main() {
+    if (r1 != 777) return 1;
+    if (r2 != '!') return 2;
+    
+    r1 = 42;
+    r2 = 'A';
+
+    if (r1 != 42) return 3;
+    if (r2 != 'A') return 4;
+    if (f.some_integer != 42) return 5;
+    if (f.c != 'A') return 6;
+
+    return 0;
+}