Hi,
I'm trying to update std.typecons.Unique. I want to add a static opCall
with no arguments to simulate a nullary-argument constructor.
Unfortunately, with a recent dmd from Git, I get this (reduced code):
class Class {}
struct U
{
Class c;
this(A...)(A args)
if (A.length != 0)
{
c = new Class(args);
}
static U opCall()
{
U u;
u.c = new Class;
return u;
}
}
$ c:\git\digger\current\bin\dmd -w -c "opcall.d" -g -gc -unittest
opcall.d(24): Error: struct opcall.U static opCall is hidden by
constructors and can never be called
opcall.d(24): Please use a factory method instead, or replace all
constructors with static opCall.
This is a new error in the next release. It seems to be this bug, marked
as WONTFIX:
https://issues.dlang.org/show_bug.cgi?id=12194
As nullary static opCall doesn't conflict with a nullary constructor (as
the latter can't exist), it would be useful to allow it. Otherwise, how
can we wrap the construction of a class with a nullary constructor?
