My compiler does not complain about this code:

enum A { a, b};
enum B { c, d};
if (a == b)        <<< I expect diagnostics here
    ;

(Yes I know enums are convertible to int, but I thought it is 'at most one
only'

Isn't it right or wrong?

Radoslav Getov



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Radoslav Getov wrote:
>
> My compiler does not complain about this code:
>
> enum A { a, b};
> enum B { c, d};
> if (a == b)        <<< I expect diagnostics here
>     ;
>
> (Yes I know enums are convertible to int, but I thought it is 'at most one
> only'

Yes, there is a limit of one user-defined conversion per conversion
sequence, but there's a seperate conversion sequence for each argument
to operator==().

In any event, you're comparing two values of the same type, so no
conversion is needed.

> Isn't it right or wrong?

Yes, of course. The important thing, of course, is know which of the two
it is.

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