On Sunday, 8 March 2015 at 01:20:57 UTC, Timothee Cour wrote:
To clarify, I'm only asking about a struct allocated via new.
Unique!T is wrapped around a struct, but it allocates a struct
T via 'new',
so my question still holds: does 'delete t' (where t is a
struct allocated
via new) guarantee deterministic destruction?
I'm guessing yes, otherwise Unique would be broken, but where
is that
specified in the docs?
And if delete is to be deprecated (according to the docs), what
is the
correct way to do that (despite fact that Unique relies on
delete).
On Sat, Mar 7, 2015 at 4:02 PM, weaselcat via
Digitalmars-d-learn <
digitalmars-d-learn@puremagic.com> wrote:
On Saturday, 7 March 2015 at 23:48:39 UTC, Timothee Cour wrote:
I'm a little confused about the following:
clear,delete,destroy.
My understanding is that clear is deprecated and delete is
planned to be
deprecated, so we should only ever use destroy (which
deterministic calls
the destructor but doesn't release memory).
Unique uses delete however in the destructor. Is that still
guaranteeing
deterministic destruction when the uniqued element is either
a class or
struct? (ie if the destructor has a file handle resource,
will it be
deterministically freed?)
structs are allocated on the stack(unless instantiated with
new), and call
their destructor when you leave their scope. Unique still
guarantees
deterministic destruction because it's wrapped around a
struct, it's a
fairly common 'D idiom' I'd say(i.e, look at how File is
implemented - D's
runtime and standard library are surprisingly well documented
and easy to
read.)
I'm not sure why Unique uses delete, might just be bitrot.
Unique!T allocates via new, but itself is meant to be allocated
on the stack. When it leaves the scope it calls delete on its
contents(if they're still valid - i.e, haven't been moved to a
different Unique!T)
delete guarantees deterministic destruction because structs
guarantee deterministic destruction, and Unique!T itself is a
struct.
http://dlang.org/cpptod.html#raii
To answer your questions,
1. Yes, Unique!T guarantees deterministic destruction of T(unless
there are bugs I'm unaware of.)
2. It's on the deprecated page.
http://dlang.org/deprecate.html#delete
