• Claudiu Verdes <claudiu.verdes gmail.com> Jun 16 2011
• bearophile <bearophileHUGS lycos.com> Jun 16 2011
• "Steven Schveighoffer" <schveiguy yahoo.com> Jun 17 2011

Claudiu Verdes <claudiu.verdes gmail.com> writes:

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Hi,

I'm new to D and trying to follow Alexandrescu's TDPL code examples I came
across an error on the code below:

class A
{
inout(int) val() inout
{
return _val; // error - see below
}
private int _val;
};

The compiler (dmd v2.052) complains on the marked line with the message
"Error: inout on return means inout must be on a parameter as well for inout
inout(int)()".

What am I doing wrong? TDPL has a very similar example...

Regards,
Claudiu

P.S. Is there a netiquette (a la C++ FAQ lite) about posting on this forum
that I should be aware of?

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Hi,<div><br></div><div>I&#39;m new to D and trying to follow Alexandrescu&#=
39;s TDPL code examples I came across an error on the code below:</div><div=
<br></div><div><div>class A</div><div>{</div><div><span class=3D"Apple-tab=


<div><span class=3D"Apple-tab-span" style=3D"white-space:pre">	</span>{</di=
v><div><span class=3D"Apple-tab-span" style=3D"white-space:pre">		</span>re=
turn _val; // error - see below</div><div><span class=3D"Apple-tab-span" st=
yle=3D"white-space:pre">	</span>}</div>
<div><span class=3D"Apple-tab-span" style=3D"white-space:pre">	</span>priva=
te int _val;</div><div>};</div></div><div><br></div><div>The compiler (dmd =
v2.052) complains on the marked line with the message &quot;Error: inout on=
 return means inout must be on a parameter as well for inout inout(int)()&q=
uot;.=A0</div>
<div><br></div><div>What am I doing wrong? TDPL has a very similar example.=
..</div><div><br></div><div>Regards,</div><div>Claudiu</div><div><br></div>=
<div>P.S. Is there a netiquette (a la C++ FAQ lite) about posting on this f=
orum that I should be aware of?</div>
<div><br></div>

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bearophile <bearophileHUGS lycos.com> writes:

Claudiu Verdes:

 What am I doing wrong? TDPL has a very similar example...


I think this TDPL example is not good. And generally inout is not fully
implemented in D yet.


 P.S. Is there a netiquette (a la C++ FAQ lite) about posting on this forum
 that I should be aware of?


I think there isn't one. Anything goes! ;-)

Bye,
bearophile

"Steven Schveighoffer" <schveiguy yahoo.com> writes:

On Thu, 16 Jun 2011 22:12:49 -0400, bearophile <bearophileHUGS lycos.com>  
wrote:

 Claudiu Verdes:

 What am I doing wrong? TDPL has a very similar example...


 I think this TDPL example is not good. And generally inout is not fully  
 implemented in D yet.


Yes, a better example would be:


class A
{
	ref inout(int) val() inout
	{
		return _val;
	}
	private int _val;
}

inout is only relevant if the data type being returned has a reference in  
it, because a value-only type is implicitly castable to any constancy  
(const, immutable, or mutable).

As bearophile says, inout is not properly implemented yet.

-Steve