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digitalmars.D - Need 'this' to access 'opCall'? Was I trying to?

reply Mehrdad <wfunction hotmail.com> writes:
struct Adder {
     int v;
     auto opCall(int x) { return x + v; }
}

auto adder(int v) {
     return Adder(v);  // How do I call the constructor??
}

int main() {
     auto a = adder(5);
}
Sep 26 2011
parent reply Trass3r <un known.com> writes:
Your opCall isn't static.
Sep 26 2011
parent reply Mehrdad <wfunction hotmail.com> writes:
On 9/26/2011 8:13 AM, Trass3r wrote:

 Your opCall isn't static.


Yeah, I don't want it to be. I want to use opCall on an instance, not on 
the type.
Sep 26 2011
parent reply Jonathan M Davis <jmdavisProg gmx.com> writes:
On Monday, September 26, 2011 09:01:20 Mehrdad wrote:

 On 9/26/2011 8:13 AM, Trass3r wrote:

 Your opCall isn't static.


 
 Yeah, I don't want it to be. I want to use opCall on an instance, not on
 the type.


Well, it looks like having declared a non-static opCall makes the 
automatically generated constructor for the struct unusable - which may or may 
not be a bug (there are similar issues with declaring opCast). If you just 
declare a constructor, it should solve the problem.

- Jonathan M Davis
Sep 26 2011
next sibling parent "Regan Heath" <regan netmail.co.nz> writes:
On Mon, 26 Sep 2011 17:14:45 +0100, Jonathan M Davis <jmdavisProg gmx.com>  
wrote:


 On Monday, September 26, 2011 09:01:20 Mehrdad wrote:

 On 9/26/2011 8:13 AM, Trass3r wrote:

 Your opCall isn't static.


 Yeah, I don't want it to be. I want to use opCall on an instance, not on
 the type.


 Well, it looks like having declared a non-static opCall makes the
 automatically generated constructor for the struct unusable - which may  
 or may
 not be a bug (there are similar issues with declaring opCast). If you  
 just
 declare a constructor, it should solve the problem.


I couldn't get that to work.. but this does:

import std.stdio;

struct Adder {
     int v;
     auto opCall(int x) { return x + v; }
}

auto adder(int v) {
	Adder a;
	a.v = v;
     return a;
}

void main() {
     auto a = adder(5);	
	writefln("%s", a(5));
}

-- 
Using Opera's revolutionary email client: http://www.opera.com/mail/
Sep 26 2011
prev sibling parent reply Trass3r <un known.com> writes:
 Well, it looks like having declared a non-static opCall makes the
 automatically generated constructor for the struct unusable - which may  
 or may not be a bug


I do think it's a bug. Only a static opCall should interfere with the  
constructor.
Sep 26 2011
parent reply Mehrdad <wfunction hotmail.com> writes:
On 9/26/2011 9:40 AM, Trass3r wrote:

 Well, it looks like having declared a non-static opCall makes the
 automatically generated constructor for the struct unusable - which 
 may or may not be a bug


 I do think it's a bug. Only a static opCall should interfere with the 
 constructor.


Yeah I agree -- should I file it as one?
Sep 26 2011
parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 26 Sep 2011 13:13:52 -0400, Mehrdad <wfunction hotmail.com> wrote:


 On 9/26/2011 9:40 AM, Trass3r wrote:

 Well, it looks like having declared a non-static opCall makes the
 automatically generated constructor for the struct unusable - which  
 may or may not be a bug


 I do think it's a bug. Only a static opCall should interfere with the  
 constructor.


 Yeah I agree -- should I file it as one?


Might want to add this case (as I think it is important, and doesn't yet  
seem to have an exact duplicate report) to bug 6036.  Looks like Kenji is  
on the case, and he usually comes up with a pull request :)

-Steve
Sep 26 2011
parent Mehrdad <wfunction hotmail.com> writes:
On 9/26/2011 10:34 AM, Steven Schveighoffer wrote:

 On Mon, 26 Sep 2011 13:13:52 -0400, Mehrdad <wfunction hotmail.com> 
 wrote:


 On 9/26/2011 9:40 AM, Trass3r wrote:

 Well, it looks like having declared a non-static opCall makes the
 automatically generated constructor for the struct unusable - which 
 may or may not be a bug


 I do think it's a bug. Only a static opCall should interfere with 
 the constructor.


 Yeah I agree -- should I file it as one?


 Might want to add this case (as I think it is important, and doesn't 
 yet seem to have an exact duplicate report) to bug 6036.  Looks like 
 Kenji is on the case, and he usually comes up with a pull request :)

 -Steve


Done!
http://d.puremagic.com/issues/show_bug.cgi?id=6036
Sep 26 2011