digitalmars.D - static member functions
- John Fletcher <J.P.Fletcher aston.ac.uk> Jun 15 2004
- Ben Hinkle <bhinkle4 juno.com> Jun 15 2004
- john bunbury28.pluc.com Jun 16 2004
- John Fletcher <J.P.Fletcher aston.ac.uk> Jun 18 2004
- Norbert Nemec <Norbert.Nemec gmx.de> Jun 18 2004
I am working with some automatically generated D interface code where
code for each C++ class being wrapped is put into a different file. The
problem is that the classes interact, and that I have a problem with
permission to see a specific static member function between classes. It
all works if the code is all in one file.
Example:
public class A {
private void* Ptr;
private static void* getPtr(A obj) {
return (obj === null) ? null : Ptr; }
}
is an extract from automatically generated code.
If a second class B has a constructor with an A as an argument the code
generated is
public class B {
// ...
public this(A a) {
// contains A.getPtr(a) which fails unless the code for B is in
the same file as the code for A.
// This applies even if I change the permission of the static
function to public.
}
}
One workaround is to put into the defintion of A the extra member
function
public void* Ptr() { return getPtr(this); }
which can be seen from the other file, i.e. putting a.Ptr() for
A.getPtr().
I am in a position to edit the code which does the automatic generation,
and the aim is to find a general solution which would result in the
generation of valid code which works. There should be no need to edit
the result.
At the moment the question is, is there a way in which the code of class
A could be altered so that class B can see A.setPtr(obj) even when they
are in separate files?
More details of the background to this are on
http://www.prowiki.org/wiki4d/wiki.cgi?DwithSwig
Thanks
John Fletcher
Jun 15 2004
Declaring getPtr as static and public should work. I recommend getting an example of the problem with as few lines as possible and post it on digitalmars.D.bugs. John Fletcher wrote:I am working with some automatically generated D interface code where code for each C++ class being wrapped is put into a different file. The problem is that the classes interact, and that I have a problem with permission to see a specific static member function between classes. It all works if the code is all in one file. Example: public class A { private void* Ptr; private static void* getPtr(A obj) { return (obj === null) ? null : Ptr; } } is an extract from automatically generated code. If a second class B has a constructor with an A as an argument the code generated is public class B { // ... public this(A a) { // contains A.getPtr(a) which fails unless the code for B is in the same file as the code for A. // This applies even if I change the permission of the static function to public. } } One workaround is to put into the defintion of A the extra member function public void* Ptr() { return getPtr(this); } which can be seen from the other file, i.e. putting a.Ptr() for A.getPtr(). I am in a position to edit the code which does the automatic generation, and the aim is to find a general solution which would result in the generation of valid code which works. There should be no need to edit the result. At the moment the question is, is there a way in which the code of class A could be altered so that class B can see A.setPtr(obj) even when they are in separate files? More details of the background to this are on http://www.prowiki.org/wiki4d/wiki.cgi?DwithSwig Thanks John Fletcher
Jun 15 2004
In article <camq9o$1sb1$1 digitaldaemon.com>, Ben Hinkle says...Declaring getPtr as static and public should work. I recommend getting an example of the problem with as few lines as possible and post it on digitalmars.D.bugs.
Thanks for the hint. It isn't a bug, but a misunderstanding of mine. The problem is that the automatically generated file has the same name as the class within it. When class A has a public static member e.g. class A { public static void* getPtr(A obj) { // something } } The structure in a class B importing a class A is that A is the module and the class is referred to as A.A import A; class B { public void* getAPtr(A obj) { return A.A.getPtr(a); // This works. } //public void* getAPtr(A obj) { // return A.getPtr(a); This fails. //} } I now need to alter the SWIG code generator for D to do the correct thing. Thanks again. John
Jun 16 2004
john bunbury28.plus.com wrote:In article <camq9o$1sb1$1 digitaldaemon.com>, Ben Hinkle says...Declaring getPtr as static and public should work. I recommend getting an example of the problem with as few lines as possible and post it on digitalmars.D.bugs.
Thanks for the hint. It isn't a bug, but a misunderstanding of mine. The problem is that the automatically generated file has the same name as the class within it. I now need to alter the SWIG code generator for D to do the correct thing. Thanks again. John
The alternative is to rename the file e.g. classA.d instead of A.d This is what I have done. John
Jun 18 2004
John Fletcher wrote:I am working with some automatically generated D interface code where code for each C++ class being wrapped is put into a different file. The problem is that the classes interact, and that I have a problem with permission to see a specific static member function between classes. It all works if the code is all in one file. Example: public class A { private void* Ptr; private static void* getPtr(A obj) { return (obj === null) ? null : Ptr; } }
It might just be a typo in the post, but still: accessing "Ptr" within a static function will not work. Instead, it should be "obj.Ptr".
Jun 18 2004









John Fletcher <J.P.Fletcher aston.ac.uk> 