[Development] QtCS 2017 QtCore sessions
Allan Sandfeld Jensen
kde at carewolf.com
Mon Dec 4 15:20:02 CET 2017
On Montag, 4. Dezember 2017 15:00:53 CET Marc Mutz wrote:
>
> Ah, well, yes. Nothing truly originates in C++, true. But, IIRC, the
> Haskell name is maybe. So why is it QOptional and not QMaybe? Because
> the C++ interface is used as the basis, not something from Haskell.
>
I believe the name "optional" comes from Haskell and Java where it appeared
first. The standard library only imports things that are already industry
standard, and once there were several implementations of optional out there,
they started to pull one in. They just didn't manage to write it without using
C++17'isms.
The other name that sometimes gets used instead of Optional is Nullable (from
SQL and C#), but that is a little different. I don't think "maybe" ever gets
used much for this kind of type.
Anyway. I do believe we should try to be compatible with std. I just don't see
the point in throwing our hands in the air and refusing to improve our base
classes while waiting for something we might be able to use 9 years from now.
Btw. One of the issues with std::expected and std::outcome is that many are
pushing for them to become C++ versions of Haskell monads, which complicates
things.
Best regard
'Allan
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