Searchable Enum-like object with string and int conversion

Question

Intro

The enum type in C++ is fairly basic; it basically just creates a bunch of compile-time values for labels (potentially with proper scoping with

Answer 1

Sometimes when you want to do something that isn't supported by the language, you should look external to the language to support it. In this case, code-generation seems like the best option.

Start with a file with your enumeration. I'll pick XML completely arbitrarily, but really any reasonable format is fine:

It's easy enough to add whatever optional fields you need in there (do you need a value? Should the enum be unscoped? Have a specified type?).

Then you write a code generator in the language of your choice that turns that file into a C++ header (or header/source) file a la:

enum class MyEnum {
    ALPHA,
    BETA,
    GAMMA,
};

std::string to_string(MyEnum e) {
    switch (e) {
    case MyEnum::ALPHA: return "ALPHA";
    case MyEnum::BETA: return "BETA";
    case MyEnum::GAMMA: return "GAMMA";
    }
}

MyEnum to_enum(const std::string& s) {
    static std::unordered_map m{
        {"ALPHA", MyEnum::ALPHA},
        ...
    };

    auto it = m.find(s);
    if (it != m.end()) {
        return it->second;
    }
    else {
        /* up to you */
    }
}

The advantage of the code generation approach is that it's easy to generate whatever arbitrary complex code you want for your enums. Basically just side-step all the problems you're currently having.