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digitalmars.D.learn - Create object from a library's Class returns Null

reply dangbinghoo <dangbinghoo gmail.com> writes:
hi there,

I have a set of DB entity class in a library and creating Object 
from another project which linked with the library returns Null.

I don't know what's wrong there.

the source is like this:

   a. I have a library with such a structure:
      gwlib/source/gwlib/entity/nsconf.d

     with content:

    --------------
     module gwlib.entity.nsconf;

     class NSconf
     {
         String name;
         ...
     }
    --------------

   b. I use this gwlib library in another project named testobj

      testobj/source/app.d :

     --------------
      import gwlib.entity.nsconf;

      void main()
      {
           writeln(Object.factory("gwlib.entity.nsconf.NSConf"));
      }
     --------------

      this print out `null`.

     dub file cofig is :
     -----------------
     "dependencies": {
		"gwlib": {"path":"../gwlib"}
     },
     -----------------

And I just tested with DMD and LDC2, the result is a little 
different, but all the two is returning a null object.

I don't know what's the reason.


Could someone help with this? Thanks!

   > I posted the dub version of the whole project on github:
     https://github.com/dangbinghoo/DObjectCreatTest
     one can just clone and reproduce the result.


-------
binghoo dang
May 28 2019
next sibling parent reply Nick Treleaven <nick geany.org> writes:
On Tuesday, 28 May 2019 at 09:25:51 UTC, dangbinghoo wrote:

 
     class NSconf
     {
         String name;
         ...
     }


Does this class have a non-default constructor?
May 28 2019
parent reply dangbinghoo <dangbinghoo gmail.com> writes:
On Tuesday, 28 May 2019 at 14:16:44 UTC, Nick Treleaven wrote:

 On Tuesday, 28 May 2019 at 09:25:51 UTC, dangbinghoo wrote:

 
     class NSconf
     {
         String name;
         ...
     }


 Does this class have a non-default constructor?


yes, I didn't provide constructor, as Class will have a default 
one if not supplied.


 Typo, should be NSconf.


yeah, I made a typo mistake in the forum post, but the code in 
github repo is really with no typo problem.

This seems to be a serious problem, I found it works when I using 
Ldc2 1.12 version even on ARM target.
May 28 2019
parent dangbinghoo <dangbinghoo gmail.com> writes:
On Tuesday, 28 May 2019 at 14:24:30 UTC, dangbinghoo wrote:

 On Tuesday, 28 May 2019 at 14:16:44 UTC, Nick Treleaven wrote:

 On Tuesday, 28 May 2019 at 09:25:51 UTC, dangbinghoo wrote:

 




 yeah, I made a typo mistake in the forum post, but the code in 
 github repo is really with no typo problem.

 This seems to be a serious problem, I found it works when I 
 using Ldc2 1.12 version even on ARM target.


hi there,

Anyone help with this?

Not a typo problem, even this
-------
	writeln(Object.factory(ns.toString()));
-------

result in `null`.

just try the github demo project:

https://github.com/dangbinghoo/DObjectCreatTest.git



Thanks!
-----------
binghoo dang
May 28 2019
prev sibling next sibling parent Nick Treleaven <nick geany.org> writes:
On Tuesday, 28 May 2019 at 09:25:51 UTC, dangbinghoo wrote:

 writeln(Object.factory("gwlib.entity.nsconf.NSConf"));


Typo, should be NSconf.
May 28 2019
prev sibling parent reply Adam D. Ruppe <destructionator gmail.com> writes:
Object.factory is pretty unreliable and has few supporters among 
the developers. I wouldn't suggest relying on it and instead 
building your own factory functions.
May 28 2019
parent reply dangbinghoo <dangbinghoo gmail.com> writes:
On Wednesday, 29 May 2019 at 02:42:23 UTC, Adam D. Ruppe wrote:

 Object.factory is pretty unreliable and has few supporters 
 among the developers. I wouldn't suggest relying on it and 
 instead building your own factory functions.


oh, that's bad news, but the hibernated library is using this 
feature. what should I do with this?
May 28 2019
parent reply dangbinghoo <dangbinghoo gmail.com> writes:
On Wednesday, 29 May 2019 at 05:04:54 UTC, dangbinghoo wrote:

 On Wednesday, 29 May 2019 at 02:42:23 UTC, Adam D. Ruppe wrote:

 Object.factory is pretty unreliable and has few supporters 
 among the developers. I wouldn't suggest relying on it and 
 instead building your own factory functions.


 oh, that's bad news, but the hibernated library is using this 
 feature. what should I do with this?


now we found that, class from a module library won't work, if I 
move gwlib to testobj/source, it works.
May 28 2019
parent dangbinghoo <dangbinghoo gmail.com> writes:
change gwlib buildtype to sourceLibrary solves the problem, but 
it should work for static or shared library.
May 29 2019