P2078 Add new traits type std::is_complex

[wg21bot]

P2078R0 Add new traits type std::is_complex (Bob Steagall)

[brycelelbach]

LEWG has this as P1 unscheduled, LEWGI will take it.

[Cpp-Lisa]

Reviewed in SG6 Monday in Prague. We generally approve the direction, but have concerns about user-provided complex types (i.e., not specialization of std::complex).

The motivating example may be better served with a more narrowly-tailored trait has_trivial_complex_conjugate.

[brycelelbach]

Prague 2020-02 LEWGI Minutes

P2078R0 std::is_complex: Direction Review

Chair: Bryce Adelstein Lelbach

Champion: Bob Steagall

Minute Taker: Ben Craig

Start Review: 2020-02-11 10:46

Should this be extensible to user-defined complex numbers?

Also looking at D2098 std::is_specialization_of.

End: 10:59

CONSENSUS: Authors have a plan for how to revise this; no guidance needed.