Switch case for Rapidjson::Type

Question

JSON that I'm trying to parse looks something like this is:

{
   "testBool": true,
   "testString": "eu"
}

And my current parser looks really ugly and it really feels like there is a more elegant way to solve this problem. I tried looking into rapidjson::Type for a switch case using document.GetObject().GetType() but it doesn't provide the same type precision that you can achieve by using Get%TypeName%() functions. hashmap is nothing but a wrapper around std::unordered_map<std::string, std::any>.

rapidjson::Document document;
document.Parse(tmp_string.c_str());

for (auto& member : document.GetObject())
{

if (member.value.IsBool())
{
   hashmap->addEntry<bool>(member.name.GetString(), member.value.GetBool());
}
else if (member.value.IsString())
{
   hashmap->addEntry<std::string>(member.name.GetString(), member.value.GetString());
}
else if (member.value.IsInt())
{
   hashmap->addEntry<int>(member.name.GetString(), member.value.GetInt());
}

.....
//And so on
.....

}

Answer 1

my current parser looks really ugly

Beauty is in the eye of the be(er)holder...here's my code:

static void
printField(const Value& e, const string& fld, bool print_newline = true) {
    const Value &v = fld.empty() ? e : e[fld];
    if (print_newline)
        cout << endl << "\t";
    if (not fld.empty())
        cout << fld << ":  ";
    if ( /* custom stuff required? */ ) {
        // Do custom stuff
    else {
       switch (v.GetType()) {
        case kNullType:
            cout << "Null";
            break;
        case kFalseType:
        case kTrueType:
            cout << v.GetBool();
            break;
        case kObjectType: {
            bool first = true;
            cout << "{ ";
            for (const auto &subfield: v.GetObject()) {
                if (first)
                    first = false;
                else
                    cout << ", ";
                printField(v, subfield.name.GetString(), false);
            }
            cout << " }";
            break;
        }
        case kArrayType: {
            bool first = true;
            cout << "[ ";
            for (const auto &arrEntry: v.GetArray()) {
                if (first)
                    first = false;
                else
                    cout << ", ";
                printField(arrEntry, "", false);
            }
            cout << " ]";
            break;
        }
        case kStringType:
            cout << v.GetString();
            break;
        case kNumberType:
            if (v.IsInt64())
                cout << v.GetInt64();
            else if (v.IsUint64())
                cout << v.GetUint64();
            else
                cout << v.GetDouble();
            break;
        default:
            stringstream msg;
            msg << "Unexpected RapidJSON Value type: " << v.GetType();
            throw logic_error(msg.str());
        }
    }
}

This uses the stringize stuff to solve some problems, but, if you don't like that, you can get the same effect manually. It subdivides the IsNumber case using a cascading if; if you need more resolution, you can add the other cases to that.