A type X meets the ConnectCondition requirements if it satisfies the requirements of Destructible (C++ 2014 [destructible]) and CopyConstructible (C++ 2014 [copyconstructible]), as well as the additional requirements listed below.
In the table below, x denotes a value of type X, ec denotes a (possibly const) value of type error_code, and ep denotes a (possibly const) value of a type satisfying the endpoint ([socket.reqmts.endpoint]) requirements.
| expression | return type | assertion/note pre/post-condition |
| x(ec, ep) | bool | Returns true to indicate that the connect or async_connect algorithm should attempt a connection to the endpoint ep. Otherwise, returns false to indicate that the algorithm should not attempt connection to the endpoint ep, and should instead skip to the next endpoint in the sequence. |