1 files changed, 82 insertions, 0 deletions
diff --git a/lib/sol2/examples/source/error_handler.cpp b/lib/sol2/examples/source/error_handler.cpp
new file mode 100644
index 0000000..6564676
--- /dev/null
+++ b/lib/sol2/examples/source/error_handler.cpp
@@ -0,0 +1,82 @@
+#define SOL_ALL_SAFETIES_ON 1
+#include <sol/sol.hpp>
+
+#include <iostream>
+
+int main () {
+
+	const auto& code = R"(
+	bark_power = 11;
+
+	function got_problems( error_msg )
+		return "got_problems handler: " .. error_msg
+	end
+
+	function woof ( bark_energy )
+		if bark_energy < 20 then
+			error("*whine*")
+		end
+		return (bark_energy * (bark_power / 4))
+	end
+
+	function woofers ( bark_energy )
+		if bark_energy < 10 then
+			error("*whine*")
+		end
+		return (bark_energy * (bark_power / 4))
+	end
+	)";
+
+	sol::state lua;
+	lua.open_libraries(sol::lib::base);
+	
+	lua.script(code);
+
+	sol::protected_function problematic_woof = lua["woof"];
+	problematic_woof.error_handler = lua["got_problems"];
+
+	auto firstwoof = problematic_woof(20);
+	if ( firstwoof.valid() ) {
+		// Can work with contents
+		double numwoof = firstwoof;
+		std::cout << "Got value: " << numwoof << std::endl;
+	}
+	else{
+		// An error has occured
+		sol::error err = firstwoof;
+		std::string what = err.what();
+		std::cout << what << std::endl;
+	}
+
+	// errors, calls handler and then returns a string error from Lua at the top of the stack
+	auto secondwoof = problematic_woof(19);
+	if (secondwoof.valid()) {
+		// Call succeeded
+		double numwoof = secondwoof;
+		std::cout << "Got value: " << numwoof << std::endl;
+	}
+	else {
+		// Call failed
+		// Note that if the handler was successfully called, this will include
+		// the additional appended error message information of
+		// "got_problems handler: " ...
+		sol::error err = secondwoof;
+		std::string what = err.what();
+		std::cout << what << std::endl;
+	}
+
+	// can also use optional to tell things
+	sol::optional<double> maybevalue = problematic_woof(19);
+	if (maybevalue) {
+		// Have a value, use it
+		double numwoof = maybevalue.value();
+		std::cout << "Got value: " << numwoof << std::endl;
+	}
+	else {
+		std::cout << "No value!" << std::endl;
+	}
+
+	std::cout << std::endl;
+
+	return 0;
+}