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digitalmars.D.learn - Is it possible to write some class members in another module ?

reply Vinod K Chandran <kcvinu82 gmail.com> writes:
Hi all,
Is it possible to write some class members in another module ? I 
have class with a lot of member variables.(probably 50+) I would 
like to write them (Not all, but some of them) in a special 
module for the sake of maintenance.
May 19 2020
next sibling parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Tuesday, 19 May 2020 at 22:01:03 UTC, Vinod K Chandran wrote:

 Is it possible to write some class members in another module ?


You can make some of members be other structs that you aggregate 
together.
May 19 2020
parent reply Vinod K Chandran <kcvinu82 gmail.com> writes:
On Tuesday, 19 May 2020 at 22:10:25 UTC, Adam D. Ruppe wrote:

 On Tuesday, 19 May 2020 at 22:01:03 UTC, Vinod K Chandran wrote:

 Is it possible to write some class members in another module ?


 You can make some of members be other structs that you 
 aggregate together.


That's a good idea but there is a problem.
As per your idea--
```
struct Events{
     uint click;
     uint shown;
     uint move;
     ....
}
class Window : Control{
    Events event;
    .....
}
// Now, we need to use like this
auto form= new Window();
form.event.click = bla_bla;

// I really want to use like this
auto form= new Window();
form.click = bla_bla;
```
May 20 2020
parent reply welkam <wwwelkam gmail.com> writes:
On Wednesday, 20 May 2020 at 09:45:48 UTC, Vinod K Chandran wrote:

 // Now, we need to use like this
 auto form= new Window();
 form.event.click = bla_bla;

 // I really want to use like this
 auto form= new Window();
 form.click = bla_bla;
 ```


Then you want alias this.

class Window : Control{
    Events event;
    alias event this
    .....
}

and now when you write
form.click = bla_bla;
Compiler first checks if form.click compiles and if it doesnt it 
then it tries form.event.click
May 20 2020
parent reply Vinod K Chandran <kcvinu82 gmail.com> writes:
On Wednesday, 20 May 2020 at 15:01:36 UTC, welkam wrote:

 On Wednesday, 20 May 2020 at 09:45:48 UTC, Vinod K Chandran 
 wrote:

 // Now, we need to use like this
 auto form= new Window();
 form.event.click = bla_bla;

 // I really want to use like this
 auto form= new Window();
 form.click = bla_bla;
 ```


 Then you want alias this.

 class Window : Control{
    Events event;
    alias event this
    .....
 }

 and now when you write
 form.click = bla_bla;
 Compiler first checks if form.click compiles and if it doesnt 
 it then it tries form.event.click


Wow !!!
What a perfect solution ! That is what i wanted. Thanks a lot 
friend. :)
The more i practice D, the more i am loving it. I am very sad 
that i delayed to start learning D only because of semicolons and 
curly braces. But now i recognizes that how beautiful this 
language is.
May 20 2020
parent welkam <wwwelkam gmail.com> writes:
On Wednesday, 20 May 2020 at 17:29:47 UTC, Vinod K Chandran wrote:

 I am very sad that i delayed to start learning D only because 
 of semicolons and curly braces.


Walter(creator of this language) said that redundant grammar is a 
good thing because it allows compiler to emit better error 
messages.
May 20 2020
prev sibling parent reply Boris Carvajal <boris2.9 gmail.com> writes:
On Tuesday, 19 May 2020 at 22:01:03 UTC, Vinod K Chandran wrote:

 Hi all,
 Is it possible to write some class members in another module ? 
 I have class with a lot of member variables.(probably 50+) I 
 would like to write them (Not all, but some of them) in a 
 special module for the sake of maintenance.


You can use Template Mixins to add variable declarations in 
others scope.

https://dlang.org/spec/template-mixin.html
May 19 2020
parent Vinod K Chandran <kcvinu82 gmail.com> writes:
On Tuesday, 19 May 2020 at 23:51:45 UTC, Boris Carvajal wrote:

 On Tuesday, 19 May 2020 at 22:01:03 UTC, Vinod K Chandran wrote:

 Hi all,
 Is it possible to write some class members in another module ? 
 I have class with a lot of member variables.(probably 50+) I 
 would like to write them (Not all, but some of them) in a 
 special module for the sake of maintenance.


 You can use Template Mixins to add variable declarations in 
 others scope.

 https://dlang.org/spec/template-mixin.html


Thank you for the reply. Let me check. :)
May 20 2020