Which operator @?

Question

The C ++ man page has a table of operators here, but I don’t understand what operator@ . For example:

@a (a) .operator@ ( ) operator@ (a) !std::cin calls std::cin.operator!()

However, there is no such operator in this language. What does it mean?

Answer 1

@ not a valid C ++ operator and is used here as a placeholder for real operators.
In short, it can be replaced with any of the actual C ++ statements, and the statement should be useful for this particular statement.

Answer 2

The cppreference page, as well as the C ++ standard, treats the @ symbol as a placeholder for real operators. It is not used for coding.