Boost json as_uint64() raise exception.

[TyeolRik]

Hello, I think I found the bug in boost::json.

boost::json::object test;
test["quota"] = 12345;
std::string key("quota");
uint64_t quota;
try {
    quota = test.at(key).as_uint64();
} catch(const std::out_of_range& e) {
    std::cout << "Cannot found the key: <" << key << "> in Body!" << std::endl;
} catch(const std::invalid_argument& e) {
    std::cout << "We found key: <" << key << "> in Body but it is " << e.what() << std::endl;
}

When I run above code, std::invalid_argument exception raised.

We found key: <quota> in Body but it is not a uint64

When I change as_uint64() to as_int64(), there is no raised exception. Is this bug? or my fault? Please guide me to solve this problem :(
* Of course, I know the difference between uint64 and int64. But, I need as_uint64() for safe. (value should be larger than 0)
** When I change the code 12345 to 12345UL, It works well without exception....

My enviornment is

• OS: CentOS 8 Stream
• G++: g++ (GCC) 11.2.1 20220127 (Red Hat 11.2.1-9)
• Boost 1.80.0

[yaojiadong]

as_uint64() does not convert a signed int to an unsigned int. It does the same as get_uint64() with exception. The value stored in the object is a signed value, that is why it throws when you try to get it as an unsigned int.

consider: quota = static_cast<uint64_t>(test.at(key).as_int64());