C++17 Token struct

cpp17_tokens.cpp

#include <cstdint>
#include <cstddef>
#include <string>
#include <iostream>

struct TokIdentifier {
    std::string name;

    TokIdentifier() = delete;
    TokIdentifier(TokIdentifier const &) = default;
    TokIdentifier(TokIdentifier &&) = default;
    TokIdentifier(std::string && name)
        : name(std::move(name))
    {}
    ~TokIdentifier() = default;
};

struct TokIntLit {
    int64_t value;
};

struct Token {
    enum class Id : uint8_t {
        Identifier,
        Equals,
        IntLit,
    } id;

    union {
        TokIdentifier ident;
        TokIntLit intlit;
    };

private:
    explicit Token(Id id)
        : id(id)
    {}
public:
    Token() = delete;
    Token(Token const &) = default;
    Token(Token && other) = default;
    Token(TokIdentifier && ident)
        : id(Id::Identifier)
        , ident(std::move(ident))
    {}
    Token(TokIntLit && intlit)
        : id(Id::IntLit)
        , intlit(std::move(intlit))
    {}
    ~Token() {
        switch (id) {
        case Id::Identifier:
            ident.~TokIdentifier();
            break;
        default:
            break;
        }
    }

    static inline Token new_identifier(std::string && name) {
        return Token{TokIdentifier{std::move(name)}};
    }

    static inline Token new_equals() {
        return Token{Id::Equals};
    }

    static inline Token new_intlit(int64_t val) {
        return Token{TokIntLit{val}};
    }
};

std::ostream &operator << (std::ostream &os, Token const &tok) {
    switch (tok.id) {
    case Token::Id::Identifier:
        os << "Identifier(\"" << tok.ident.name << "\")";
        break;
    case Token::Id::Equals:
        os << '=';
        break;
    case Token::Id::IntLit:
        os << "IntLit(" << tok.intlit.value << ')';
        break;
    }
    return os;
}

int main() {
    Token const tokens[] = {
        Token::new_identifier("my_var"),
        Token::new_equals(),
        Token::new_intlit(123),
    };

    for (auto const &t : tokens) {
        std::cout << t << '\n';
    }
}