...

examples/device_exam.cpp

@@ -6,7 +6,7 @@ using namespace adc;
 
 int main()
 {
-    std::string id1 = "1", id2 = "2";
+    std::string id1 = "1", id2 = "2", id3 = "str";
 
     int i = 10;
     double d = 8.1;
@@ -32,6 +32,19 @@ int main()
     std::println("add RO-attr with id='{}' (val={})", id2, d);
     dev.addAttr(id2, [&d]() -> adc_result_t<double> { return d; }, nullptr);
 
+    std::println("add RW-attr with id='{}' (val={})", id3, s);
+    dev.addAttr(
+        id3, [&s]() -> adc_result_t<std::string> { return s; },
+        [&s](std::string const& sv) -> adc_error_t {
+            s = sv;
+            return {};
+        },
+        [&s](adc_result_t<std::string> const&) -> adc_result_t<const char*> { return s.c_str(); },
+        [&s](adc_result_t<const char*> const& p) -> adc_result_t<std::string> {
+            s = p.value();
+            return s;
+        });
+
     std::print("get '{}'-attr value as native int:\t", id1);
     adc_result_t<int> ri = dev[id1];
     if (ri) {