On Monday, 5 May 2014 at 00:44:43 UTC, Caligo via Digitalmars-d
wrote:
On Sun, May 4, 2014 at 12:22 AM, Andrei Alexandrescu via
Digitalmars-d <
digitalmars-d@puremagic.com> wrote:
The on/off switch may be a nice idea in the abstract but is
hardly the
perfect recipe to good language feature development; otherwise
everybody
would be using it, and there's not overwhelming evidence to
that. (I do
know it's been done a few times, such as the (in)famous "new
scoping rule
of the for statement" for C++ which has been introduced as an
option by
VC++.)
No, it's nothing abstract, and it's very practical and useful.
Rust has
such a thing, #![feature(X,Y,Z)]. So does Haskell, with {-#
feature #-}.
Even Python has __future__, and many others.
Well, python __future__ it's not exactly that: it's for
introducing changes that are impacting the actual codebase...
It's some sort of extreme care for not braking anything out there.
/Paolo
