How to compare std::variant of custom classes?

Question

1.It's my classes:

struct SymbolToken {
    std::string name;
};

struct QuoteToken {
};

struct ConstantToken {
    int value;
};

2. I have a following typedef:

typedef std::variant<SymbolToken, QuoteToken, ConstantToken> Token;

3. I wanna write an assert:

assert(Token{ConstantToken{4}} == Token{ConstantToken{4}}) // fine
assert(Token{ConstantToken{3}} == Token{ConstantToken{4}}) // exception

How can I implement it?

Assert failure rarely throws an exception? – Yakk - Adam Nevraumont Nov 02 '18 at 02:09 — Yakk - Adam Nevraumont, Nov 02 '18 at 02:09

score 2 · Accepted Answer · answered Nov 02 '18 at 02:08

2

Implement == on the contained types.

For Quote, always return true.

Probably also implement != as a matter of sanity.

answered Nov 02 '18 at 02:08

1 Answers1