add 'onselect' callback & remove 'default' tag

src/logic/scripting/scripting_functional.cpp

@@ -69,6 +69,17 @@ wstringconsumer scripting::create_wstring_consumer(
     };
 }
 
+stringconsumer scripting::create_string_consumer(
+    const scriptenv& env, const std::string& src, const std::string& file
+) {
+    return [=](const std::string& x) {
+        if (auto L = process_callback(env, src, file)) {
+            lua::pushstring(L, x);
+            lua::call_nothrow(L, 1);
+        }
+    };
+}
+
 wstringsupplier scripting::create_wstring_supplier(
     const scriptenv& env, const std::string& src, const std::string& file
 ) {

src/logic/scripting/scripting_functional.hpp

@@ -23,6 +23,12 @@ namespace scripting {
         const std::string& file = "[string]"
     );
 
+    stringconsumer create_string_consumer(
+        const scriptenv& env,
+        const std::string& src,
+        const std::string& file = "[string]"
+    );
+
     wstringconsumer create_wstring_consumer(
         const scriptenv& env,
         const std::string& src,