Is it possible to convert raw string value of enum to enum?

[StormLord07]

Whilst i was able to find a way to serialize enum to string, I now need to deserialize a string to enum from lets say a database.

from example to serialize we do

Color color = Color::Red;
std::string buffer{};
glz::write<glz::opts{.raw = true}>(color, buffer);
expect(buffer == "Red");

That works great, but as soon as i tried to deserialize I couldn't find a way.

So far i tried

Color color{};
std::string buffer{"Red"};

glz::read<glz::opts{}>(color, buffer);
glz::read<glz::opts{}>(buffer, color);
glz::read<glz::opts{}>(buffer);

none seem to work, is there such functionality?

glz::meta for that enum was defined

[stephenberry]

Using .raw = true will serialize without quotes. It seems like in your use case this is producing invalid JSON (an unquoted string). What are you wanting your JSON to look like? Glaze is only concerned with parsing valid JSON.

[StormLord07]

I have same enums in my DB stored as strings, i want to do something like

struct SomeJson {
    ...
    Color color{};
    ...
};

Color color_enum;
std::string color = ValueFromDB();

glz::read<glz::opts{}>(color, color_enum);

SomeJson{.color = color_enum};
...
glz::write_json(SomeJson).value_or("error");

Lets assume that the color in DB is string "Red", then the output json would be something like {..., "color": "Red", ...}

So i just want to get enum repr of my string.

[stephenberry]

Are you using enumerate with glz::meta like this:

enum class Color { Red, Green, Blue };

template <>
struct glz::meta<Color> {
   using enum Color;
   static constexpr auto value = enumerate(Red,
                                           Green,
                                           Blue
   );
};

[StormLord07]

Yes like this,
Also tried with explicitly providing names e.g
("Red", Color::Red, ...)

[stephenberry]

I think you might be confused thinking this is a quoted string: std::string buffer{"Red"};, but this would be a quoted string: std::string buffer{R"("Red")"}; or std::string buffer{"\"Red\""};

[StormLord07]

Okay, i might not be very good at explaining myself, what i need to do is the opposite of
glz::write<glz::opts{.raw=true}>(color, buff);

or in just if else

std::string val = getColorFromDB();
Color color{};

if (val == "Red") {
    color = Color::Red;
} else if (val == "Blue") {
    color = Color::Blue;
} else if (...) {
...
}

Where val is not quoted string

[stephenberry]

So, you're getting your enum from your database as a non-quoted string and want to get it into an enum value again. You could add quotes to make it a valid JSON string and then glz::read will work. Or, you could use a library like simple_enum, which also has support for working with Glaze.