A few more examples

example/examples.cpp

@@ -98,6 +98,137 @@ assert(r == 11);
 (void)r;
 }
 
+
+#include <iostream>
+#include <boost/type_index.hpp>
+
+namespace quick_examples_ns {
+
+//[pfr_quick_examples_structures
+struct foo {
+    int integer;
+    double real;
+    
+    void operator +=(int v) {
+        integer += v * 10;
+        real += v * 100;
+    }
+};
+
+struct bar {
+    char character;
+    foo f;
+};
+
+bar var{'A', {777, 3.141593}};
+//]
+    
+inline std::ostream& operator<<(std::ostream& os, const bar& b) {
+    return os << '{' << b.character << ", {" << b.f.integer << ", " << b.f.real << "}}";
+}
+
+void test_examples() {
+  {
+    bar var{'A', {777, 3.141593}};
+    
+//[pfr_quick_examples_flat_for_each
+    // incrementing each field on 1:
+    boost::pfr::flat_for_each_field(var, [](auto& field) {
+        field += 1;
+    });
+//]
+    
+    std::cout << "flat_for_each_field outputs:\n" << var << '\n';
+  }
+    
+  {  
+    bar var{'A', {777, 3.141593}};
+    
+//[pfr_quick_examples_for_each    
+    // incrementing first field on 1 and calling foo::operator+= for second field:
+    boost::pfr::for_each_field(var, [](auto& field) {
+        field += 1;
+    });
+//]
+    
+    std::cout << "flat_for_each_field outputs:\n" << var << '\n';
+  }
+
+
+
+  
+  {
+    bar var{'A', {777, 3.141593}};
+    
+//[pfr_quick_examples_flat_for_each_idx  
+    boost::pfr::flat_for_each_field(var, [](const auto& field, std::size_t idx) {
+        std::cout << idx << ": " << boost::typeindex::type_id_runtime(field) << '\n';
+    });
+//]
+  }
+    
+  {
+    bar var{'A', {777, 3.141593}};
+
+//[pfr_quick_examples_for_each_idx  
+    boost::pfr::for_each_field(var, [](const auto& field, std::size_t idx) {
+        std::cout << idx << ": " << boost::typeindex::type_id_runtime(field) << '\n';
+    });
+//]
+  }
+
+
+  {
+//[pfr_quick_examples_tuple_size
+    std::cout << "tuple_size: " << boost::pfr::tuple_size<bar>::value << '\n';
+//]
+  }
+    
+  {    
+//[pfr_quick_examples_flat_tuple_size
+    std::cout << "flat_tuple_size: " << boost::pfr::flat_tuple_size<bar>::value << '\n';
+//]
+  }
+
+#if __cplusplus >= 201606L /* Oulu meeting, not the exact value */
+  {
+    bar var{'A', {777, 3.141593}};
+//[pfr_quick_examples_get_1
+    boost::pfr::get<1>(var) = foo{1, 2}; // C++17 is required
+//]
+    std::cout << "boost::pfr::get<1>(var) outputs:\n" << var << '\n';
+  }
+#endif
+
+  {
+    bar var{'A', {777, 3.141593}};
+//[pfr_quick_examples_flat_get_1
+    boost::pfr::flat_get<1>(var) = 1;
+//]
+    std::cout << "boost::pfr::flat_get<1>(var) outputs:\n" << var << '\n';
+  }
+  
+  
+  {
+    bar var{'A', {777, 3.141593}};
+//[pfr_quick_examples_get_2
+    boost::pfr::get<1>(var.f) = 42.01;
+//]
+    std::cout << "boost::pfr::get<1>(var.f) outputs:\n" << var << '\n';
+  }
+
+  {
+    bar var{'A', {777, 3.141593}};
+//[pfr_quick_examples_flat_get_2
+    boost::pfr::flat_get<1>(var.f) = 42.01;
+//]
+    std::cout << "boost::pfr::flat_get<1>(var.f) outputs:\n" << var << '\n';
+  }
+}
+
+} // namespace for_each_field_ex
+
 int main() {
     example_get();
+    quick_examples_ns::test_examples();
 }