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#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.set_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;
}
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