On Thursday, 29 November 2012 at 17:12:29 UTC, jerro wrote:
The original idea is that there should be *no such thing* as
default construction of a struct as being anything other than
T.init. The default construction of a struct should be a
compile time creature, not a runtime one.
Any methods or workarounds to try and make T() produce
something different from T.init is bad D practice. The
compiler tries to statically head them off, but probably
should do a better job of that.
The only reason to associate no parameter constructors with
default values is because of how C++ works. There is no reason
why
Foo foo; (1)
should be equivalent to
auto foo = Foo(); (2)
in D. We could allow constructors with no parameters and make
(1) equivalent to
auto foo = Foo.init; (3)
The current workaround when one wants (2) to construct the
object at runtime is to define a static opCall, but that's
messy and inconsistent. It's just one more quirk one needs to
learn to effectively use the language.
This do not solve problem with heap allocated struct being moved,
but is definitively the right direction.
