Re: Is this a bug when creating proxies in classes?
On Monday, 25 August 2014 at 18:10:33 UTC, Gary Willoughby wrote:
class Foo
{
private int foo;
mixin Proxy!(foo);
this(int x)
{
this.foo = x;
}
}
Apparently Proxy doesn't work correctly inside classes.
Is wrapping something inside a class particularly useful?
Please comment on https://issues.dlang.org/show_bug.cgi?id=13623.
Re: Is this a bug when creating proxies in classes?
On Tuesday, 26 August 2014 at 20:41:47 UTC, Marc Schütz wrote: On Tuesday, 26 August 2014 at 18:13:52 UTC, Gary Willoughby wrote: With that in mind what is strange is that if in my example you change the class for a struct everything works as expected. Why is that? This is bizarre... I tried a few things, but I have no idea. At first I thought the `static if` that calls `isArray` is inside another `static if`, but this is not the case. Might be a compiler bug? Anyone else know or can reduce this if it's a bug?
Re: Is this a bug when creating proxies in classes?
On Tuesday, 26 August 2014 at 18:13:52 UTC, Gary Willoughby wrote:
With that in mind what is strange is that if in my example you
change the class for a struct everything works as expected. Why
is that?
That's because when not mixed into a class, Proxy did import
std.traits:
static if (!is(typeof(this) == class))
{
private import std.traits;
Re: Is this a bug when creating proxies in classes?
On Thursday, 28 August 2014 at 16:23:48 UTC, anonymous wrote:
On Tuesday, 26 August 2014 at 18:13:52 UTC, Gary Willoughby
wrote:
With that in mind what is strange is that if in my example you
change the class for a struct everything works as expected.
Why is that?
That's because when not mixed into a class, Proxy did import
std.traits:
static if (!is(typeof(this) == class))
{
private import std.traits;
Ah right, yes. ta.
Re: Is this a bug when creating proxies in classes?
On Monday, 25 August 2014 at 21:14:42 UTC, Ali Çehreli wrote: On 08/25/2014 12:17 PM, Marc Schütz schue...@gmx.net wrote: On Monday, 25 August 2014 at 19:12:48 UTC, Marc Schütz wrote: On Monday, 25 August 2014 at 18:44:36 UTC, Ali Çehreli wrote: It can be explained if the mixed-in template is evaluated at the mixin context without bringing in the imported modules to that context. I don't know whether it is true or whether it is a known limitation. You're right, that's it! It works when I import std.traits first. So... the fix is to import std.traits inside template Proxy. Going to submit a PR. https://github.com/D-Programming-Language/phobos/pull/2463 Thanks! And I learned from you in the pull request the following fact: quote Quoting http://dlang.org/template-mixin : Unlike a template instantiation, a template mixin's body is evaluated within the scope where the mixin appears, not where the template declaration is defined. It is analogous to cutting and pasting the body of the template into the location of the mixin. /quote Ali With that in mind what is strange is that if in my example you change the class for a struct everything works as expected. Why is that?
Re: Is this a bug when creating proxies in classes?
On Tuesday, 26 August 2014 at 18:13:52 UTC, Gary Willoughby wrote: With that in mind what is strange is that if in my example you change the class for a struct everything works as expected. Why is that? This is bizarre... I tried a few things, but I have no idea. At first I thought the `static if` that calls `isArray` is inside another `static if`, but this is not the case. Might be a compiler bug?
Is this a bug when creating proxies in classes?
Compiling the following code:
import std.typecons;
class Foo
{
private int foo;
mixin Proxy!(foo);
this(int x)
{
this.foo = x;
}
}
void main()
{
}
Produces this error:
:!rdmd --force -de -debug -w test.d
/usr/include/dmd/phobos/std/typecons.d(4043): Error: template
instance isArray!(typeof(a)) template 'isArray' is not defined
test.d(7): Error: mixin test.Foo.Proxy!(foo) error instantiating
Failed: [dmd, -de, -debug, -w, -v, -o-, test.d,
-I.]
Can anyone else confirm or am i doing something wrong. I'm using
DMD 2.066.0 64bit Ubuntu 14.04.
Re: Is this a bug when creating proxies in classes?
On 08/25/2014 11:10 AM, Gary Willoughby wrote:
Compiling the following code:
import std.typecons;
class Foo
{
private int foo;
mixin Proxy!(foo);
this(int x)
{
this.foo = x;
}
}
void main()
{
}
Produces this error:
:!rdmd --force -de -debug -w test.d
/usr/include/dmd/phobos/std/typecons.d(4043): Error: template instance
isArray!(typeof(a)) template 'isArray' is not defined
test.d(7): Error: mixin test.Foo.Proxy!(foo) error instantiating
Failed: [dmd, -de, -debug, -w, -v, -o-, test.d, -I.]
Can anyone else confirm or am i doing something wrong. I'm using DMD
2.066.0 64bit Ubuntu 14.04.
isArray is defined in std.traits. I don't know why it doesn't work even
though std.typecons does import it.
The workaround is to import it yourself in your program:
import std.traits;
Ali
Re: Is this a bug when creating proxies in classes?
On Monday, 25 August 2014 at 18:10:33 UTC, Gary Willoughby wrote: :!rdmd --force -de -debug -w test.d /usr/include/dmd/phobos/std/typecons.d(4043): Error: template instance isArray!(typeof(a)) template 'isArray' is not defined test.d(7): Error: mixin test.Foo.Proxy!(foo) error instantiating Failed: [dmd, -de, -debug, -w, -v, -o-, test.d, -I.] Can anyone else confirm or am i doing something wrong. I'm using DMD 2.066.0 64bit Ubuntu 14.04. It stopped working after this PR was merged: https://github.com/D-Programming-Language/phobos/pull/1899 But I suspect that something else is going on. The PR only introduced the call to `isArray` into `std.typecons.Proxy`.
Re: Is this a bug when creating proxies in classes?
On 08/25/2014 11:38 AM, Marc Schütz schue...@gmx.net wrote: On Monday, 25 August 2014 at 18:10:33 UTC, Gary Willoughby wrote: :!rdmd --force -de -debug -w test.d /usr/include/dmd/phobos/std/typecons.d(4043): Error: template instance isArray!(typeof(a)) template 'isArray' is not defined test.d(7): Error: mixin test.Foo.Proxy!(foo) error instantiating Failed: [dmd, -de, -debug, -w, -v, -o-, test.d, -I.] Can anyone else confirm or am i doing something wrong. I'm using DMD 2.066.0 64bit Ubuntu 14.04. It stopped working after this PR was merged: https://github.com/D-Programming-Language/phobos/pull/1899 But I suspect that something else is going on. The PR only introduced the call to `isArray` into `std.typecons.Proxy`. It can be explained if the mixed-in template is evaluated at the mixin context without bringing in the imported modules to that context. I don't know whether it is true or whether it is a known limitation. Ali
Re: Is this a bug when creating proxies in classes?
On Monday, 25 August 2014 at 18:44:36 UTC, Ali Çehreli wrote: It can be explained if the mixed-in template is evaluated at the mixin context without bringing in the imported modules to that context. I don't know whether it is true or whether it is a known limitation. You're right, that's it! It works when I import std.traits first. So... the fix is to import std.traits inside template Proxy. Going to submit a PR.
Re: Is this a bug when creating proxies in classes?
On Monday, 25 August 2014 at 19:12:48 UTC, Marc Schütz wrote: On Monday, 25 August 2014 at 18:44:36 UTC, Ali Çehreli wrote: It can be explained if the mixed-in template is evaluated at the mixin context without bringing in the imported modules to that context. I don't know whether it is true or whether it is a known limitation. You're right, that's it! It works when I import std.traits first. So... the fix is to import std.traits inside template Proxy. Going to submit a PR. https://github.com/D-Programming-Language/phobos/pull/2463
Re: Is this a bug when creating proxies in classes?
On 08/25/2014 12:17 PM, Marc Schütz schue...@gmx.net wrote: On Monday, 25 August 2014 at 19:12:48 UTC, Marc Schütz wrote: On Monday, 25 August 2014 at 18:44:36 UTC, Ali Çehreli wrote: It can be explained if the mixed-in template is evaluated at the mixin context without bringing in the imported modules to that context. I don't know whether it is true or whether it is a known limitation. You're right, that's it! It works when I import std.traits first. So... the fix is to import std.traits inside template Proxy. Going to submit a PR. https://github.com/D-Programming-Language/phobos/pull/2463 Thanks! And I learned from you in the pull request the following fact: quote Quoting http://dlang.org/template-mixin : Unlike a template instantiation, a template mixin's body is evaluated within the scope where the mixin appears, not where the template declaration is defined. It is analogous to cutting and pasting the body of the template into the location of the mixin. /quote Ali
